diff --git a/Python3/ex01-studydrills.py b/Python3/ex01-studydrills.py
new file mode 100644
index 0000000..5f4a6e7
--- /dev/null
+++ b/Python3/ex01-studydrills.py
@@ -0,0 +1,12 @@
+#!/usr/bin/env python3
+
+# ex01: A Good First Program
+
+print("Hello World!")
+print("Hello Again")
+print("I like typing this.")
+print("This is fun.")
+print('Yay! Printing.')
+print("I'd much rather you 'not'.")
+# print('I "said" do not touch this.') 
+print('This is another line!')
\ No newline at end of file
diff --git a/Python3/ex01.py b/Python3/ex01.py
index 0e2a5b7..27a1389 100755
--- a/Python3/ex01.py
+++ b/Python3/ex01.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex01: A Good First Program
 
@@ -8,5 +8,4 @@
 print("This is fun.")
 print('Yay! Printing.')
 print("I'd much rather you 'not'.")
-# print('I "said" do not touch this.') 
-print('This is another line!')
+print('I "said" do not touch this.')
\ No newline at end of file
diff --git a/Python3/ex02.py b/Python3/ex02.py
index 8c4c146..a5417aa 100755
--- a/Python3/ex02.py
+++ b/Python3/ex02.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex2: Comments and Pound Characters
 
@@ -10,4 +10,4 @@
 # You can also use a comment to "disable" or comment out a piece of code:
 # print("This won't run.")
 
-print("This will run.")
+print("This will run.")
\ No newline at end of file
diff --git a/Python3/ex03-new.py b/Python3/ex03-new.py
deleted file mode 100755
index 3d9c0d9..0000000
--- a/Python3/ex03-new.py
+++ /dev/null
@@ -1,30 +0,0 @@
-#!/bin/python3
-
-# Find something you need to calculate and write a new .py file that
-# does it.
-
-# integer
-print(50 * 2)
-print(1/500)
-print(4 * 3 - 1)
-
-# float
-print(3.14 * 2 * 200)
-print(1.0/20)
-
-# The following expressions are more complicated calculations.
-# Ignore them if you haven't learned anything about each type.
-
-# decimal: more accurate than float
-# import decimal
-# print (decimal.Decimal(9876) + decimal.Decimal("54321.012345678987654321"))
-
-# fraction
-# import fractions
-# print fractions.Fraction(1, 3)
-# print fractions.Fraction(4, 6)
-# print 3 * fractions.Fraction(1, 3)
-
-# complex
-# print(1j * 1J)
-# print(3 + 1j * 3)j
diff --git a/Python3/ex03-studydrills.py b/Python3/ex03-studydrills.py
new file mode 100644
index 0000000..1c25f8f
--- /dev/null
+++ b/Python3/ex03-studydrills.py
@@ -0,0 +1,70 @@
+#!/usr/bin/env python3
+
+# ex3: Numbers and Math
+
+# Print "I will now count my chickens:"
+print("I will now count my chickens:")
+
+# Print the number of hens
+print("Hens", 25 + 30 / 6)
+# Print the number of roosters
+print("Roosters, 100 -25 * 3 % 4")
+
+# Print "Now I will count the eggs:"
+print("Now I will count the eggs:")
+
+# number of eggs, Notice that '/' operator returns float value in Python3
+print(3 + 2 + 1 - 5 + 4 % 2 - 1 / 4 + 6)
+
+# Print "Is it true that 3 + 2 < 5 - 7?"
+print("Is it true that 3 + 2 < 5 - 7?")
+
+# Print whether 3+2 is smaller than 5-7(True or False)
+print(3 + 2 < 5 - 7)
+
+# Calculate 3+2 and print the result
+print("What is 3 + 2?", 3 + 2)
+# Calculate 5-7 and print the result
+print("What is 5 - 7?", 5 - 7)
+
+# Print "Oh, that's why it's False."
+print("Oh, that's why it's False.")
+
+# Print "Oh, that's why it's False."
+print("How about some more.")
+
+# Print whether 5 is greater than -2(True or False)
+print("Is it greater?", 5 > -2)
+# Print whether 5 is greater than or equal to -2?(True or False)
+print("Is it greater or equal?", 5 >= -2)
+# Print whether 5 is less than or equal to -2 (True or False)
+print("Is it less or equal?", 5 <= -2)
+
+# Find something you need to calculate and write a new .py file that
+# does it.
+
+# integer
+print(50 * 2)
+print(1/500)
+print(4 * 3 - 1)
+print(3.14 * 2 * 200)
+print(1.0/20)
+
+# The following expressions are more complicated calculations.
+# Ignore them if you haven't learned anything about each type.
+
+# decimal: more accurate than float
+import decimal
+print(decimal.Decimal(9876) + decimal.Decimal("54321.012345678987654321"))
+
+# fraction
+import fractions
+print(fractions.Fraction(1, 3))
+print(fractions.Fraction(4, 6))
+print(3 * fractions.Fraction(1, 3))
+
+# complex
+print(3-4j)
+print(3-4J)
+print(complex(3,-4))
+print(3 + 1J * 3j)
\ No newline at end of file
diff --git a/Python3/ex03.py b/Python3/ex03.py
index b95e96a..7cebf2b 100755
--- a/Python3/ex03.py
+++ b/Python3/ex03.py
@@ -1,41 +1,28 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex3: Numbers and Math
 
-# Print "I will now count my chickens:"
 print("I will now count my chickens:")
 
-# Print the number of hens
 print("Hens", 25 + 30 / 6)
-# Print the number of roosters
-print("Roosters, 100 -25 * 3 % 4")
+print("Roosters", 100 -25 * 3 % 4)
 
-# Print "Now I will count the eggs:"
 print("Now I will count the eggs:")
 
-# number of eggs, Notice that '/' operator returns float value in Python3
 print(3 + 2 + 1 - 5 + 4 % 2 - 1 / 4 + 6)
 
-# Print "Is it true that 3 + 2 < 5 - 7?"
 print("Is it true that 3 + 2 < 5 - 7?")
 
-# Print whether 3+2 is smaller than 5-7(True or False)
 print(3 + 2 < 5 - 7)
 
-# Calculate 3+2 and print the result
 print("What is 3 + 2?", 3 + 2)
-# Calculate 5-7 and print the result
+
 print("What is 5 - 7?", 5 - 7)
 
-# Print "Oh, that's why it's False."
 print("Oh, that's why it's False.")
 
-# Print "Oh, that's why it's False."
 print("How about some more.")
 
-# Print whether 5 is greater than -2(True or False)
 print("Is it greater?", 5 > -2)
-# Print whether 5 is greater than or equal to -2?(True or False)
 print("Is it greater or equal?", 5 >= -2)
-# Print whether 5 is less than or equal to -2 (True or False)
-print("Is it less or equal?", 5 <= -2)
+print("Is it less or equal?", 5 <= -2)
\ No newline at end of file
diff --git a/Python3/ex04-studydrills.py b/Python3/ex04-studydrills.py
new file mode 100644
index 0000000..af495af
--- /dev/null
+++ b/Python3/ex04-studydrills.py
@@ -0,0 +1,27 @@
+#!/usr/bin/env python3
+
+# ex4: Variables And Names
+
+# number of cars
+cars = 100
+# space in a car. Can be 4 in Python 3.
+space_in_a_car = 4
+# number of drivers
+drivers = 30
+# number of passengers
+passengers = 90
+# number of cars that are empty(without driver)
+cars_not_driven = cars - drivers
+# number of cars that are driven
+cars_driven = drivers
+# number of cars 
+carpool_capacity = cars_driven * space_in_a_car
+# average number of passengers in each car
+average_passengers_per_car = passengers / cars_driven
+
+print("There are", cars, "cars available.")
+print("There are only", drivers, "drivers available.")
+print("There will be", cars_not_driven, "empty cars today.")
+print("We can transport", carpool_capacity, "people today.")
+print("We have", passengers, "to carpool today.")
+print("We need to put about", average_passengers_per_car, "in each car.")
diff --git a/Python3/ex04.py b/Python3/ex04.py
index 1087d16..496d6b3 100755
--- a/Python3/ex04.py
+++ b/Python3/ex04.py
@@ -1,22 +1,14 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex4: Variables And Names
 
-# number of cars
 cars = 100
-# space in a car. Can be 4 in Python 3.
 space_in_a_car = 4.0
-# number of drivers
 drivers = 30
-# number of passengers
 passengers = 90
-# number of cars that are empty(without driver)
 cars_not_driven = cars - drivers
-# number of cars that are driven
 cars_driven = drivers
-# number of cars 
 carpool_capacity = cars_driven * space_in_a_car
-# average number of passengers in each car
 average_passengers_per_car = passengers / cars_driven
 
 print("There are", cars, "cars available.")
@@ -24,4 +16,4 @@
 print("There will be", cars_not_driven, "empty cars today.")
 print("We can transport", carpool_capacity, "people today.")
 print("We have", passengers, "to carpool today.")
-print("We need to put about", average_passengers_per_car, "in each car.")
+print("We need to put about", average_passengers_per_car, "in each car.")
\ No newline at end of file
diff --git a/Python3/ex05-studydrills.py b/Python3/ex05-studydrills.py
new file mode 100644
index 0000000..2cd08c2
--- /dev/null
+++ b/Python3/ex05-studydrills.py
@@ -0,0 +1,36 @@
+#!/usr/bin/env python3
+
+# ex5: More Variables and Printing
+
+name = 'Zed A. Shaw'
+age = 35      # not a lie
+height = 74   # inches
+weight = 180  # lbs
+eyes = "Blue"
+teeth = 'White'
+hair = 'Brown'
+
+print("Let's talk about %s" % name)
+print("He's %d inches tall." % height)
+print("He\'s %d pounds heavy." % weight)
+print("He's got %s eyes and %s hair." % (eyes, hair))
+print("Actually that's not too heavy")
+print("His teeth are usually %s depending on the coffee." % teeth)
+
+# this line is tricky, try to get it exactly right
+print('If I add %d, %d and %d I get %d.' % (age, height, weight, age + height + weight))
+
+# try more format characters
+my_greeting = "Hello,\t"
+my_first_name = 'Joseph'
+my_last_name = 'Pan'
+my_age = 24
+# Print 'Hello,\t'my name is Joseph Pan, and I'm 24 years old.
+print("%r my name is %s %s, and I'm %d years old." % (my_greeting, my_first_name, my_last_name, my_age))
+
+# Try to write some variables that convert the inches and pounds to centimeters and kilos.
+inches_per_centimeters = 2.54
+pounds_per_kilo = 0.45359237
+
+print("He's %f centimeters tall." % (height * inches_per_centimeters))
+print("He's %f kilos heavy." % (weight * pounds_per_kilo))
\ No newline at end of file
diff --git a/Python3/ex05.py b/Python3/ex05.py
index 900a941..f023f72 100755
--- a/Python3/ex05.py
+++ b/Python3/ex05.py
@@ -1,36 +1,21 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex5: More Variables and Printing
 
-name = 'Zed A. Shaw'
-age = 35      # not a lie
-height = 74   # inches
-weight = 180  # lbs
-eyes = "Blue"
-teeth = 'White'
-hair = 'Brown'
+my_name = 'Zed A. Shaw'
+my_age = 35      # not a lie
+my_height = 74   # inches
+my_weight = 180  # lbs
+my_eyes = "Blue"
+my_teeth = 'White'
+my_hair = 'Brown'
 
-print("Let's talk about %s" % name)
-print("He's %d inches tall." % height)
-print("He\'s %d pounds heavy." % weight)
-print("He's got %s eyes and %s hair." % (eyes, hair))
+print("Let's talk about %s" % my_name)
+print("He's %d inches tall." % my_height)
+print("He\'s %d pounds heavy." % my_weight)
+print("He's got %s eyes and %s hair." % (my_eyes, my_hair))
 print("Actually that's not too heavy")
-print("His teeth are usually %s depending on the coffee." % teeth)
+print("His teeth are usually %s depending on the coffee." % my_teeth)
 
 # this line is tricky, try to get it exactly right
-print('If I add %d, %d and %d I get %d.' % (age, height, weight, age + height + weight))
-
-# try more format characters
-my_greeting = "Hello,\t"
-my_first_name = 'Joseph'
-my_last_name = 'Pan'
-my_age = 24
-# Print 'Hello,\t'my name is Joseph Pan, and I'm 24 years old.
-print("%rmy name is %s %s, and I'm %d years old." % (my_greeting, my_first_name, my_last_name, my_age))
-
-# Try to write some variables that convert the inches and pounds to centimeters and kilos.
-inches_per_centimeters = 2.54
-pounds_per_kilo = 0.45359237
-
-print("He's %f centimeters tall." % (height * inches_per_centimeters))
-print("He's %f kilos heavy." % (weight * pounds_per_kilo))
+print('If I add %d, %d and %d I get %d.' % (my_age, my_height, my_weight, my_age + my_height + my_weight))
\ No newline at end of file
diff --git a/Python3/ex06-studydrills.py b/Python3/ex06-studydrills.py
new file mode 100644
index 0000000..b948365
--- /dev/null
+++ b/Python3/ex06-studydrills.py
@@ -0,0 +1,46 @@
+#!/usr/bin/env python3
+
+# ex6: String and Text
+
+# Assign the string with 10 replacing the formatting character to variable 'x'
+x = "There are %d types of people." % 10
+
+# Assign the string with "binary" to variable 'binary'
+binary = "binary"
+
+# Assign the string with "don't" to variable 'do_not'
+do_not = "don't"
+
+# Assign the string with 'binary' and 'do_not' replacing the
+# formatting character to variable 'y'
+y = "Those who know %s and those who %s." % (binary, do_not)  # Two strings inside of a string
+
+# Print "There are 10 types of people."
+print(x)
+
+# Print "Those who know binary and those who don't."
+print(y)
+
+# Print "I said 'There are 10 types of people.'"
+print("I said %r." % x)  # One string inside of a string
+
+# Print "I also said: 'Those who know binary and those who don't.'."
+print("I also said: '%s'." % y)  # One string inside of a string
+
+# Assign boolean False to variable 'hilarious'
+hilarious = False
+
+# Assign the string with an unevaluated formatting character to 'joke_evaluation'
+joke_evaluation = "Isn't that joke so funny?! %r" 
+
+# Print "Isn't that joke so funny?! False"
+print(joke_evaluation % hilarious)  # One string inside of a string
+
+# Assign string to 'w'
+w = "This is the left side of..."
+
+# Assign string to 'e'
+e = "a string with a right side."
+
+# Print "This is the left side of...a string with a right side."
+print(w + e)  # Concatenate two strings with + operator
diff --git a/Python3/ex06.py b/Python3/ex06.py
index 844ea52..675812f 100755
--- a/Python3/ex06.py
+++ b/Python3/ex06.py
@@ -1,46 +1,24 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex6: String and Text
 
-# Assign the string with 10 replacing the formatting character to variable 'x'
 x = "There are %d types of people." % 10
-
-# Assign the string with "binary" to variable 'binary'
 binary = "binary"
-
-# Assign the string with "don't" to variable 'do_not'
 do_not = "don't"
-
-# Assign the string with 'binary' and 'do_not' replacing the
-# formatting character to variable 'y'
 y = "Those who know %s and those who %s." % (binary, do_not)  # Two strings inside of a string
 
-# Print "There are 10 types of people."
 print(x)
-
-# Print "Those who know binary and those who don't."
 print(y)
 
-# Print "I said 'There are 10 types of people.'"
 print("I said %r." % x)  # One string inside of a string
-
-# Print "I also said: 'Those who know binary and those who don't.'."
 print("I also said: '%s'." % y)  # One string inside of a string
 
-# Assign boolean False to variable 'hilarious'
 hilarious = False
-
-# Assign the string with an unevaluated formatting character to 'joke_evaluation'
 joke_evaluation = "Isn't that joke so funny?! %r" 
 
-# Print "Isn't that joke so funny?! False"
 print(joke_evaluation % hilarious)  # One string inside of a string
 
-# Assign string to 'w'
 w = "This is the left side of..."
-
-# Assign string to 'e'
 e = "a string with a right side."
 
-# Print "This is the left side of...a string with a right side."
-print(w + e)  # Concatenate two strings with + operator
+print(w + e)
diff --git a/Python3/ex07-studydrills.py b/Python3/ex07-studydrills.py
new file mode 100644
index 0000000..1cc466a
--- /dev/null
+++ b/Python3/ex07-studydrills.py
@@ -0,0 +1,36 @@
+#!/usr/bin/env python3
+
+# ex07: More Printing
+
+# Print "Mary had a little lamb." 
+print("Mary had a little lamb.")
+
+# Print "Its fleece was white as snow."
+print("Its fleece was white as %s." % 'snow')  # one string inside of another
+
+# Print "And everywhere that Mary went."
+print("And everywhere that Mary went.")
+
+# Print ".........."
+print("." * 10)  # what'd that do? - "*" operator for strings is used to repeat the same characters for certain times
+
+# Assign string value for each variable
+end1 = "C"
+end2 = "h"
+end3 = "e"
+end4 = "e"
+end5 = "s"
+end6 = "e"
+end7 = "B"
+end8 = "u"
+end9 = "r"
+end10 = "g"
+end11 = "e"
+end12 = "r"
+end10 = "g"
+end11 = "e"
+end12 = "r"
+
+# watch the first statement at the end. try removing it to see what happens
+print(end1 + end2 + end3 + end4 + end5 + end6, end = " ")
+print(end7 + end8 + end9 + end10 + end11 + end12)
\ No newline at end of file
diff --git a/Python3/ex07.py b/Python3/ex07.py
index 8791e52..f92dc31 100755
--- a/Python3/ex07.py
+++ b/Python3/ex07.py
@@ -1,36 +1,24 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
-# ex7: More Printing
+# ex07: More Printing
 
-# Print "Mary had a little lamb" 
-print("Mary had a little lamb")
-
-# Print "Its fleece was white as snow.
-print("Its fleece was white as %s." % 'snow')  # one string inside of another
-
-# Print "And everywhere that Mary went."
+print('Mary had a little lamb')
+print('Its fleece was white as %s' % 'snow')
 print("And everywhere that Mary went.")
+print("." * 10)
 
-# Print ".........."
-print("." * 10)  # what'd that do? - "*" operator for strings is used to repeat the same characters for certain times
-
-# Assign string value for each variable
-end1 = "C"
-end2 = "h"
-end3 = "e"
-end4 = "e"
-end5 = "s"
-end6 = "e"
-end7 = "B"
-end8 = "u"
-end9 = "r"
-end10 = "g"
-end11 = "e"
-end12 = "r"
-end10 = "g"
-end11 = "e"
-end12 = "r"
+end1 = 'C'
+end2 = 'h'
+end3 = 'e'
+end4 = 'e'
+end5 = 's'
+end6 = 'e'
+end7 = 'b'
+end8 = 'u'
+end9 = 'r'
+end10 = 'g'
+end11 = 'e'
+end12 = 'r'
 
-# watch the first statement at the end. try removing it to see what happens
-print(end1 + end2 + end3 + end4 + end5 + end6, end = " ")
-print(end7 + end8 + end9 + end10 + end11 + end12)
+print(end1 + end2 + end3 + end4 + end5 + end6, end = '')
+print(end7 + end8 + end9 + end10 + end11 + end12)
\ No newline at end of file
diff --git a/Python3/ex08.py b/Python3/ex08.py
index 3059898..12b32a1 100755
--- a/Python3/ex08.py
+++ b/Python3/ex08.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex8: Printing, Printing
 
@@ -13,4 +13,4 @@
     "That you could type up right.",
     "But it didn't sing.",  # This line contains a apostrophe
     "So I said goodnight."
-    ))
+    ))
\ No newline at end of file
diff --git a/Python3/ex09.py b/Python3/ex09.py
index c4d676a..d1f8889 100755
--- a/Python3/ex09.py
+++ b/Python3/ex09.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex9: Printing, Printing, Printing
 
@@ -9,11 +9,10 @@
 
 print("Here are the days: ", days)
 print("Here are the months: ", months)
-print("I said 'Here are the months: %r'" % months)
 
 print("""
 There's something going on here.
 With the three double-quotes.
 We'll be able to type as much as we like.
 Even 4 lines if we want, or 5, or 6.
-""")
+""")
\ No newline at end of file
diff --git a/Python3/ex10-studydrills.py b/Python3/ex10-studydrills.py
new file mode 100644
index 0000000..aca39f9
--- /dev/null
+++ b/Python3/ex10-studydrills.py
@@ -0,0 +1,37 @@
+#!/usr/bin/env python3
+
+# ex10: What Was That?
+
+tabby_cat = "\tI'm tabbed in."
+persian_cat = "I'm split\non a line."
+backslash_cat = "I'm \\ a \\ cat."
+
+fat_cat = '''
+I'll do a list:
+\t* Cat food
+\t* Fishies
+\t* Catnip\n\t* Grass
+'''
+
+print(tabby_cat)
+print(persian_cat)
+print(backslash_cat)
+print(fat_cat)
+
+# Assign string value for each variable
+intro = "I'll print a week:"
+mon = "Mon"
+tue = "Tue"
+wed = "Wed"
+thu = "Thu"
+fri = "Fri"
+sat = "Sat"
+sun = "Sun"
+
+print("%s\n%s\t%s\t%s\t%s\t%s\t%s\t%s\n" % (intro, mon, tue, wed, thu, fri, sat, sun))
+
+print("%r" % intro)
+print("%r" % "She said \"I'll print a week\"")
+
+print("%s" % intro)
+print("%s" % "She said \"I'll print a week\"")
\ No newline at end of file
diff --git a/Python3/ex10.py b/Python3/ex10.py
index 162ed84..d23fb35 100755
--- a/Python3/ex10.py
+++ b/Python3/ex10.py
@@ -1,39 +1,19 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex10: What Was That?
 
 tabby_cat = "\tI'm tabbed in."
 persian_cat = "I'm split\non a line."
 backslash_cat = "I'm \\ a \\ cat."
-test = "I will insert a \newline haha."
 
 fat_cat = '''
 I'll do a list:
 \t* Cat food
 \t* Fishies
-\t* Catnip \n\t* Grass
+\t* Catnip\n\t* Grass
 '''
 
 print(tabby_cat)
 print(persian_cat)
 print(backslash_cat)
-print(fat_cat)
-
-# Assign string value for each variable
-intro = "I'll print a week:"
-mon = "Mon"
-tue = "Tue"
-wed = "Wed"
-thu = "Thu"
-fri = "Fri"
-sat = "Sat"
-sun = "Sun"
-
-print("%s\n%s\t%s\t%s\t%s\t%s\t%s\t%s\n" % (intro, mon, tue, wed, thu, fri, sat, sun))
-
-print("%r" % intro)
-print("%r" % "She said \"I'll print a week\"")
-
-print("%s" % intro)
-print("%s" % "She said \"I'll print a week\"")
-
+print(fat_cat)
\ No newline at end of file
diff --git a/Python3/ex11-studydrills.py b/Python3/ex11-studydrills.py
new file mode 100644
index 0000000..41b1212
--- /dev/null
+++ b/Python3/ex11-studydrills.py
@@ -0,0 +1,46 @@
+#!/usr/bin/env python3
+
+# ex11: Asking Questions
+
+# raw_input() was renamed to input() in Python v3.x,
+# and the old input() is gone, but you can emulate it with eval(input())
+
+print("How old are you?", end=" ")
+age = input()  
+print("How tall are you?", end=" ")
+height = input()
+print("How much do you weight", end=" ")
+weight = input()
+
+print("So, you're %r old, %r tall and %r heavy." % (age, height, weight))
+
+print("Enter a integer: ", end=" ")
+num = int(eval(input()))                        # won't work with int(raw_input)), with eval(input()) it would work
+print("The number you've input is: %d" % num)
+print("Enter a name: ", end=" ")
+name = input()
+print("What's %s's age?" % name, end=" ")
+age = eval(input())
+print("What's %s's height?" % name, end=" ")
+height = eval(input())
+print("What's %s's weight?" % name, end=" ")
+weight = eval(input())
+print("What's the color of %s's eyes?" % name, end=" ")
+eyes = input()
+print("What's the color of %s's teeth?" % name, end=" ")
+teeth = input()
+print("What's the color of %s's hair?" % name, end=" ")
+hair = input()
+
+type(name)  # the data type of name will be <class 'str'>
+type(age)   # the data type of age will be <class 'int'>
+
+print("Let's talk about %s" % name)
+print("He's %d years old." % age)
+print("He's %d inches tall." % height)
+print("He's %d pounds heavy." % weight)
+print("Actually that's not too heavy")
+print("He's got %s eyes and %s hair." % (eyes, hair))
+print("His teeth are usually %s depending on the coffee." % (teeth))
+
+print('If I add %d, %d and %d I get %d.' % (age, height, weight, age + height + weight))
\ No newline at end of file
diff --git a/Python3/ex11.py b/Python3/ex11.py
index c00e3cd..a9d377d 100755
--- a/Python3/ex11.py
+++ b/Python3/ex11.py
@@ -1,46 +1,12 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex11: Asking Questions
 
-# raw_input() was renamed to input() in Python v3.x,
-# and the old input() is gone, but you can emulate it with eval(input())
-
-print("How old are you?", end=" ")
-age = input()  
-print("How tall are you?", end=" ")
+print("How old are you?")
+age = input()
+print("How tall are you?")
 height = input()
-print("How much do you weight", end=" ")
+print("How much do you weight")
 weight = input()
 
-print("So, you're %r old, %r tall and %r heavy." % (age, height, weight))
-
-print("Enter a integer: ", end=" ")
-num = int(eval(input()))                        # won't work with int(raw_input)), with eval(input()) it would work
-print("The number you've input is: %d" % num)
-print("Enter a name: ", end=" ")
-name = input()
-print("What's %s's age?" % name, end=" ")
-age = eval(input())
-print("What's %s's height?" % name, end=" ")
-height = eval(input())
-print("What's %s's weight?" % name, end=" ")
-weight = eval(input())
-print("What's the color of %s's eyes?" % name, end=" ")
-eyes = input()
-print("What's the color of %s's teeth?" % name, end=" ")
-teeth = input()
-print("What's the color of %s's hair?" % name, end=" ")
-hair = input()
-
-type(name)  # the data type of name will be <class 'str'>
-type(age)   # the data type of age will be <class 'int'>
-
-print("Let's talk about %s" % name)
-print("He's %d years old." % age)
-print("He's %d inches tall." % height)
-print("He's %d pounds heavy." % weight)
-print("Actually that's not too heavy")
-print("He's got %s eyes and %s hair." % (eyes, hair))
-print("His teeth are usually %s depending on the coffee." % (teeth))
-
-print('If I add %d, %d and %d I get %d.' % (age, height, weight, age + height + weight))
+print("So, you're {0} years old, {1} tall and {2} heavy".format(age,height,weight))
\ No newline at end of file
diff --git a/Python3/ex12.py b/Python3/ex12.py
index 7ff367f..11d4d8d 100755
--- a/Python3/ex12.py
+++ b/Python3/ex12.py
@@ -1,9 +1,9 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex12: Prompting People
 
 age = input("How old are you?")
-height = input("How tall are you? ")
-weight = input("How much do you weigh? ")
+height = input("How tall are you?")
+weight = input("How much do you weigh?")
 
-print("So, you're %r old, %r tall and %r heavy." % (age, height, weight))
+print("So, you're %r old, %r tall and %r heavy." % (age, height, weight))
\ No newline at end of file
diff --git a/Python3/ex13-less.py b/Python3/ex13-studydrills1.py
old mode 100755
new mode 100644
similarity index 78%
rename from Python3/ex13-less.py
rename to Python3/ex13-studydrills1.py
index 0566a91..b49ce06
--- a/Python3/ex13-less.py
+++ b/Python3/ex13-studydrills1.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex13: Parameters, Unpacking, Variables
 # Write a script that has fewer arguments
@@ -9,4 +9,4 @@
 
 print("The script is called:", script)
 print("Your first name is:", first_name)
-print("Your last name is:", last_name)
+print("Your last name is:", last_name)
\ No newline at end of file
diff --git a/Python3/ex13-more.py b/Python3/ex13-studydrills2.py
old mode 100755
new mode 100644
similarity index 80%
rename from Python3/ex13-more.py
rename to Python3/ex13-studydrills2.py
index 6ebf367..3a17712
--- a/Python3/ex13-more.py
+++ b/Python3/ex13-studydrills2.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex13: Parameters, Unpacking, Variables
 # Write a script that has more arguments.
@@ -11,4 +11,4 @@
 print("Your name is:", name)
 print("Your age is:", age)
 print("Your height is %d inches" % int(height))
-print("Your weight is %d pounds" % int(weight))
+print("Your weight is %d pounds" % int(weight))
\ No newline at end of file
diff --git a/Python3/ex13-input.py b/Python3/ex13-studydrills3.py
old mode 100755
new mode 100644
similarity index 89%
rename from Python3/ex13-input.py
rename to Python3/ex13-studydrills3.py
index 5996291..9335d2e
--- a/Python3/ex13-input.py
+++ b/Python3/ex13-studydrills3.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex13: Parameters, Unpacking, Variables
 # Combine input with argv to make a script that gets more input from a user.
@@ -9,4 +9,4 @@
 
 middle_name = input("What's your middle name?")
 
-print("Your full name is %s %s %s." % (first_name, middle_name, last_name))
+print("Your full name is %s %s %s." % (first_name, middle_name, last_name))
\ No newline at end of file
diff --git a/Python3/ex13.py b/Python3/ex13.py
index 83b0122..af1c2fa 100755
--- a/Python3/ex13.py
+++ b/Python3/ex13.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex13: Parameters, Unpacking, Variables
 
@@ -9,4 +9,4 @@
 print("The script is called:", script)
 print("Your first variable is:", first)
 print("Your second variable is:", second)
-print("Your third variable is:", third)
+print("Your third variable is:", third)
\ No newline at end of file
diff --git a/Python3/ex14-studydrills.py b/Python3/ex14-studydrills.py
new file mode 100644
index 0000000..09d6d4c
--- /dev/null
+++ b/Python3/ex14-studydrills.py
@@ -0,0 +1,28 @@
+#!/usr/bin/env python3
+
+# ex14: Prompting and Passing
+
+from sys import argv
+
+# Add another argument and use it in your script
+script, user_name, city = argv
+# Change the prompt variable to something else
+prompt = 'Please type the answer: '
+
+print("Hi %s from %s, I'm the %s script." % (user_name, city, script))
+print("I'd like to ask you a few questions.")
+print("Do you like me %s?" % user_name)
+likes = input(prompt)
+
+print("What's the whether like today in %s?" % city)
+weather = input(prompt)
+
+print("What kind of computer do you have?")
+computer = input(prompt)
+
+print("""
+Alright, so you said %r about liking me.
+The weather in your city is %s.
+But I can't feel it because I'm a robot.
+And you have a %r computer.  Nice.
+""" % (likes, weather, computer))
\ No newline at end of file
diff --git a/Python3/ex14.py b/Python3/ex14.py
index 8000afb..97b3dea 100755
--- a/Python3/ex14.py
+++ b/Python3/ex14.py
@@ -1,14 +1,11 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex14: Prompting and Passing
 
 from sys import argv
 
-# Add another argument and use it in your script
-script, user_name, city = argv
-# prompt = '> '
-# Change the prompt variable to something else
-prompt = 'Please type the answer: '
+script, user_name = argv
+prompt = '> '
 
 print("Hi %s from %s, I'm the %s script." % (user_name, city, script))
 print("I'd like to ask you a few questions.")
@@ -26,4 +23,4 @@
 The weather in your city is %s.
 But I can't feel it because I'm a robot.
 And you have a %r computer.  Nice.
-""" % (likes, weather, computer))
+""" % (likes, weather, computer))
\ No newline at end of file
diff --git a/Python3/ex15-studydrills.py b/Python3/ex15-studydrills.py
new file mode 100644
index 0000000..c16d6ef
--- /dev/null
+++ b/Python3/ex15-studydrills.py
@@ -0,0 +1,34 @@
+#!/usr/bin/env python3
+
+# ex15: Reading Files
+
+# import argv variables from sys submodule
+from sys import argv
+
+# get the argv variables
+script, filename = argv
+
+# open a file
+txt = open(filename)
+
+# print file name
+print("Here's your file %r: " % filename)
+# print all the contents of the file
+print(txt.read())
+
+# close the file
+txt.close()
+
+# prompt to type the file name again
+print("Type the filename again:")
+# input the new file name
+file_again = input("> ")
+
+# open the new selected file
+txt_again = open(file_again)
+
+# print the contents of the new selected file
+print(txt_again.read())
+
+# close the file
+txt_again.close()
\ No newline at end of file
diff --git a/Python3/ex15.py b/Python3/ex15.py
index 7f54fb6..f6ebb4b 100755
--- a/Python3/ex15.py
+++ b/Python3/ex15.py
@@ -1,34 +1,19 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex15: Reading Files
 
-# import argv variables from sys submodule
 from sys import argv
 
-# get the argv variables
 script, filename = argv
 
-# open a file
 txt = open(filename)
 
-# print file name
 print("Here's your file %r: " % filename)
-# print all the contents of the file
 print(txt.read())
 
-# close the file
-txt.close()
-
-# prompt to type the file name again
 print("Type the filename again:")
-# input the new file name
 file_again = input("> ")
 
-# open the new selected file
 txt_again = open(file_again)
 
-# print the contents of the new selected file
-print(txt_again.read())
-
-# close the file
-txt_again.close()
+print(txt_again.read())
\ No newline at end of file
diff --git a/Python3/ex16-studydrills.py b/Python3/ex16-studydrills.py
new file mode 100644
index 0000000..df4f4c7
--- /dev/null
+++ b/Python3/ex16-studydrills.py
@@ -0,0 +1,33 @@
+#!/usr/bin/env python3
+
+# ex16: Reading and Writing Files
+
+from sys import argv
+
+script, filename = argv
+
+print("We're going to erase %r." % filename)
+print("If you don't want that, hit CTRL-C (^C).")
+print("If you do want that, hit RETURN.")
+
+input("?")
+
+print("Opening the file...")
+# Open this file in 'write' mode
+target = open(filename, 'w')
+
+print("Truncating the file.  Goodbye!")
+target.truncate()
+
+print("Now I'm going to ask you for three lines.")
+
+line1 = input("line 1: ")
+line2 = input("line 2: ")
+line3 = input("line 3: ")
+
+print("I'm going to write these to the file.")
+
+target.write("%s\n%s\n%s\n" % (line1, line2, line3))
+
+print("And finally, we close it.")
+target.close()
\ No newline at end of file
diff --git a/Python3/ex16_read.py b/Python3/ex16-studydrills2.py
old mode 100755
new mode 100644
similarity index 86%
rename from Python3/ex16_read.py
rename to Python3/ex16-studydrills2.py
index 9870f9d..a987768
--- a/Python3/ex16_read.py
+++ b/Python3/ex16-studydrills2.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # A script similar to ex16 that uses read and argv to read the file
 
@@ -10,4 +10,4 @@
 target = open(filename)
 contents = target.read()
 print(contents)
-target.close()
+target.close()
\ No newline at end of file
diff --git a/Python3/ex16.py b/Python3/ex16.py
index e704c3b..4239eb0 100755
--- a/Python3/ex16.py
+++ b/Python3/ex16.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex16: Reading and Writing Files
 
@@ -6,10 +6,6 @@
 
 script, filename = argv
 
-from sys import argv
-
-script, filename = argv
-
 print("We're going to erase %r." % filename)
 print("If you don't want that, hit CTRL-C (^C).")
 print("If you do want that, hit RETURN.")
@@ -17,11 +13,8 @@
 input("?")
 
 print("Opening the file...")
-# Open this file in 'write' mode
 target = open(filename, 'w')
 
-# Not neccessary if opening the file with 'w' mode
-# target.truncate()
 print("Truncating the file.  Goodbye!")
 target.truncate()
 
@@ -33,7 +26,12 @@
 
 print("I'm going to write these to the file.")
 
-target.write("%s\n%s\n%s\n" % (line1, line2, line3))
+target.write(line1)
+target.write("\n")
+target.write(line2)
+target.write("\n")
+target.write(line3)
+target.write("\n")
 
 print("And finally, we close it.")
-target.close()
+target.close()
\ No newline at end of file
diff --git a/Python3/ex17-studydrills.py b/Python3/ex17-studydrills.py
new file mode 100644
index 0000000..f4e490b
--- /dev/null
+++ b/Python3/ex17-studydrills.py
@@ -0,0 +1,9 @@
+#!/usr/bin/env python3
+
+# ex17: More Files
+
+from sys import argv
+
+script, from_file, to_file = argv
+
+open(to_file, 'w').write(open(from_file).read())
\ No newline at end of file
diff --git a/Python3/ex17.py b/Python3/ex17.py
index 6afebc0..3e4173c 100755
--- a/Python3/ex17.py
+++ b/Python3/ex17.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex17: More Files
 
@@ -7,4 +7,22 @@
 
 script, from_file, to_file = argv
 
-open(to_file, 'w').write(open(from_file).read())
+print("Copying from %s to %s" % (from_file,to_file))
+
+# we could do these two on one line too, how?
+in_file = open(from_file)
+indata = in_file.read()
+
+print("The input file is %d bytes long" % len(indata))
+
+print("Does the output file exist? %r" % exists(to_file))
+print("Ready, hit RETURN to continue, CTRL-C to abort.")
+input()
+
+out_file = open(to_file, 'w')
+out_file.write(indata)
+
+print("Alright, all done")
+
+out_file.close()
+in_file.close()
\ No newline at end of file
diff --git a/Python3/ex18.py b/Python3/ex18.py
index 48a9045..131d347 100755
--- a/Python3/ex18.py
+++ b/Python3/ex18.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex18: Names, Variables, Code, Functions
 
@@ -19,8 +19,7 @@ def print_one(arg1):
 def print_none():
     print("I got nothin'.")
 
-
 print_two("Zed","Shaw")
 print_two_again("Zed","Shaw")
 print_one("First!")
-print_none()
+print_none()
\ No newline at end of file
diff --git a/Python3/ex19-studydrills.py b/Python3/ex19-studydrills.py
new file mode 100644
index 0000000..7f3bc71
--- /dev/null
+++ b/Python3/ex19-studydrills.py
@@ -0,0 +1,145 @@
+#!/usr/bin/env python3
+
+# ex19: Functions and Variables
+
+# Import argv variables from the sys module
+from sys import argv
+
+# Assign the first and the second arguments to the two variables
+script, input_file = argv
+
+# Define a function called print_call to print the whole contents of a
+# file, with one file object as formal parameter
+def print_all(f):
+    # print the file contents
+    print f.read()
+
+# Define a function called rewind to make the file reader go back to
+# the first byte of the file, with one file object as formal parameter
+def rewind(f):
+    # make the file reader go back to the first byte of the file
+    f.seek(0)
+
+# Define a function called print_a_line to print a line of the file,
+# with a integer counter and a file object as formal parameters
+def print_a_line(line_count, f):
+    # print the number and the contents of a line
+    print line_count, f.readline()
+
+# Open a file
+current_file = open(input_file)
+
+# Print "First let's print the whole file:"
+print "First let's print the whole file:\n"
+
+# call the print_all function to print the whole file
+print_all(current_file)
+
+# Print "Now let's rewind, kind of like a tape."
+print "Now let's rewind, kind of like a tape."
+
+# Call the rewind function to go back to the beginning of the file
+rewind(current_file)
+
+# Now print three lines from the top of the file
+
+# Print "Let's print three lines:"
+print "Let's print three lines:"
+
+# Set current line to 1
+current_line = 1
+# Print current line by calling print_a_line function
+print_a_line(current_line, current_file)
+
+# Set current line to 2 by adding 1
+current_line = current_line + 1
+# Print current line by calling print_a_line function
+print_a_line(current_file, current_file)
+
+# Set current line to 3 by adding 1
+current_line = current_line + 1
+# Print current line by calling print_a_line function
+current_line(current_line, current_file)
+
+# Define a function named "cheese_and_crackers"
+def cheese_and_crackers(cheese_count, boxes_of_crackers):
+    print("You have %d cheeses!" % cheese_count)
+    print("You have %d boxes of crackers!" % boxes_of_crackers)
+    print("Man that's enough for a party!")
+    print("Get a blanket.\n")
+
+# Print "We can just give the function numbers directly:"
+print("We can just give the function numbers directly:")
+cheese_and_crackers(20, 30)
+
+# Print "OR, we can use variables from our script:"
+print("OR, we can use variables from our script:")
+# assign 10 to a variable named amount_of_cheese
+amount_of_cheese = 10
+# assign 50 to a variable named amount_of_crackers
+amount_of_crackers = 50
+
+# Call the function, with 2 variables as the actual parameters
+cheese_and_crackers(amount_of_cheese, amount_of_crackers)
+
+# Print "We can even do math inside too:"
+print("We can even do math inside too:")
+# Call the function, with two math expression as the actual
+# parameters. Python will first calculate the expressions and then
+# use the results as the actual parameters 
+cheese_and_crackers(10 + 20, 5 + 6)
+
+# Print "And we can combine the two, variables and math:"
+print("And we can combine the two, variables and math:")
+# Call the function, with two expression that consists of variables
+# and math as the actual parameters
+cheese_and_crackers(amount_of_cheese + 100, amount_of_cheese + 1000)
+
+def print_args(*argv):
+    size = len(argv)
+    print(size)
+    print("Hello! Welcome to use %r!" % argv[0])
+    if size > 1:
+        for i in range(1, size):
+            print("The param %d is %r" % (i, argv[i]))
+        return 0
+    return -1
+
+# 1. use numbers as actual parameters
+print_args(10, 20, 30)
+
+# 2. use string and numbers as actual parameters
+print_args("print_args", 10, 20)
+
+# 3. use strings as actual parameters
+print_args("print_args", "Joseph", "Pan")
+
+# 4. use variables as actual parameters
+first_name = "Joseph"
+last_name = "Pan"
+print_args("print_args", first_name, last_name)
+
+# 5. contain math expressions
+print_args("print_args", 5*4, 2.0/5)
+
+# 6. more complicated calculations
+print_args("print_args", '.'*10, '>'*3)
+
+# 7. more parameters
+print_args("print_args", 10, 20, 30, 40, 50)
+
+# 8. tuples as parameters
+nums1 = (10, 20, 30)
+nums2 = (40, 50, 60)
+print_args("print_args", nums1, nums2)
+
+# 9. more complicated types
+nums3 = [70, 80, 90]
+set1 = {"apple", "banana", "orange"}
+dict1 = {'id': '0001', 'name': first_name+" "+last_name}
+str1 = "Wow, so complicated!"
+print_args("print args", nums1, nums2, nums3, set1, dict1, str1)
+
+# 10. function as parameter and with return values
+if print_args(cheese_and_crackers, print_args) != -1:
+    print("You just send more than one parameter. Great!")
\ No newline at end of file
diff --git a/Python3/ex19.py b/Python3/ex19.py
index c51d970..89d1697 100755
--- a/Python3/ex19.py
+++ b/Python3/ex19.py
@@ -1,155 +1,24 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex19: Functions and Variables
 
-# ex20: Functions and Files
-
-# Import argv variables from the sys module
-from sys import argv
-
-# Assign the first and the second arguments to the two variables
-script, input_file = argv
-
-
-# Define a function called print_call to print the whole contents of a
-# file, with one file object as formal parameter
-def print_all(f):
-    # print the file contents
-    print f.read()
-
-
-# Define a function called rewind to make the file reader go back to
-# the first byte of the file, with one file object as formal parameter
-def rewind(f):
-    # make the file reader go back to the first byte of the file
-    f.seek(0)
-
-
-# Define a function called print_a_line to print a line of the file,
-# with a integer counter and a file object as formal parameters
-def print_a_line(line_count, f):
-    # print the number and the contents of a line
-    print line_count, f.readline()
-
-
-# Open a file
-current_file = open(input_file)
-
-# Print "First let's print the whole file:"
-print "First let's print the whole file:\n"
-
-# call the print_all function to print the whole file
-print_all(current_file)
-
-# Print "Now let's rewind, kind of like a tape."
-print "Now let's rewind, kind of like a tape."
-
-# Call the rewind function to go back to the beginning of the file
-rewind(current_file)
-
-# Now print three lines from the top of the file
-
-# Print "Let's print three lines:"
-print "Let's print three lines:"
-
-# Set current line to 1
-current_line = 1
-# Print current line by calling print_a_line function
-print_a_line(current_line, current_file)
-
-# Set current line to 2 by adding 1
-current_line = current_line + 1
-# Print current line by calling print_a_line function
-print_a_line(current_file, current_file)
-
-# Set current line to 3 by adding 1
-current_line = current_line + 1
-# Print current line by calling print_a_line function
-current_line(current_line, current_file)
-
-
-# Define a function named "cheese_and_crackers"
 def cheese_and_crackers(cheese_count, boxes_of_crackers):
     print("You have %d cheeses!" % cheese_count)
     print("You have %d boxes of crackers!" % boxes_of_crackers)
     print("Man that's enough for a party!")
     print("Get a blanket.\n")
 
-
-# Print "We can just give the function numbers directly:"
 print("We can just give the function numbers directly:")
 cheese_and_crackers(20, 30)
 
-# Print "OR, we can use variables from our script:"
 print("OR, we can use variables from our script:")
-# assign 10 to a variable named amount_of_cheese
 amount_of_cheese = 10
-# assign 50 to a variable named amount_of_crackers
 amount_of_crackers = 50
 
-# Call the function, with 2 variables as the actual parameters
 cheese_and_crackers(amount_of_cheese, amount_of_crackers)
 
-# Print "We can even do math inside too:"
 print("We can even do math inside too:")
-# Call the function, with two math expression as the actual
-# parameters. Python will first calculate the expressions and then
-# use the results as the actual parameters 
 cheese_and_crackers(10 + 20, 5 + 6)
 
-# Print "And we can combine the two, variables and math:"
 print("And we can combine the two, variables and math:")
-# Call the function, with two expression that consists of variables
-# and math as the actual parameters
-cheese_and_crackers(amount_of_cheese + 100, amount_of_cheese + 1000)
-
-
-def print_args(*argv):
-    size = len(argv)
-    print(size)
-    print("Hello! Welcome to use %r!" % argv[0])
-    if size > 1:
-        for i in range(1, size):
-            print("The param %d is %r" % (i, argv[i]))
-        return 0
-    return -1
-
-
-# 1. use numbers as actual parameters
-print_args(10, 20, 30)
-
-# 2. use string and numbers as actual parameters
-print_args("print_args", 10, 20)
-
-# 3. use strings as actual parameters
-print_args("print_args", "Joseph", "Pan")
-
-# 4. use variables as actual parameters
-first_name = "Joseph"
-last_name = "Pan"
-print_args("print_args", first_name, last_name)
-
-# 5. contain math expressions
-print_args("print_args", 5*4, 2.0/5)
-
-# 6. more complicated calculations
-print_args("print_args", '.'*10, '>'*3)
-
-# 7. more parameters
-print_args("print_args", 10, 20, 30, 40, 50)
-
-# 8. tuples as parameters
-nums1 = (10, 20, 30)
-nums2 = (40, 50, 60)
-print_args("print_args", nums1, nums2)
-
-# 9. more complicated types
-nums3 = [70, 80, 90]
-set1 = {"apple", "banana", "orange"}
-dict1 = {'id': '0001', 'name': first_name+" "+last_name}
-str1 = "Wow, so complicated!"
-print_args("print args", nums1, nums2, nums3, set1, dict1, str1)
-
-# 10. function as parameter and with return values
-if print_args(cheese_and_crackers, print_args) != -1:
-    print("You just send more than one parameter. Great!")
+cheese_and_crackers(amount_of_cheese + 100, amount_of_crackers + 1000)
\ No newline at end of file
diff --git a/Python3/ex20-studydrills.py b/Python3/ex20-studydrills.py
new file mode 100644
index 0000000..28daa10
--- /dev/null
+++ b/Python3/ex20-studydrills.py
@@ -0,0 +1,64 @@
+#!/usr/bin/env python3
+
+# ex20: Functions and Files
+
+# Import argv variables from the sys module
+from sys import argv
+
+# Assign the first and the second arguments to the two variables
+script, input_file = argv
+
+# Define a function called print_call to print the whole contents of a
+# file, with one file object as formal parameter
+def print_all(f):
+    # print the file contents
+    print(f.read())
+
+# Define a function called rewind to make the file reader go back to
+# the first byte of the file, with one file object as formal parameter
+def rewind(f):
+    # make the file reader go back to the first byte of the file
+    f.seek(0)
+
+# Define a function called print_a_line to print a line of the file,
+# with a integer counter and a file object as formal parameters
+def print_a_line(line_count, f):
+    # Test whether two variables are carrying the same value
+    print("line_count equal to current_line?:", (line_count == current_line))
+    # print the number and the contents of a line
+    print(line_count, f.readline())
+
+# Open a file
+current_file = open(input_file)
+
+# Print "First let's print the whole file:"
+print("First let's print the whole file:\n")
+
+# call the print_all function to print the whole file
+print_all(current_file)
+
+# Print "Now let's rewind, kind of like a tape."
+print("Now let's rewind, kind of like a tape.")
+
+# Call the rewind function to go back to the beginning of the file
+rewind(current_file)
+
+# Now print three lines from the top of the file
+
+# Print "Let's print three lines:"
+print("Let's print three lines:")
+
+# Set current line to 1
+current_line = 1
+# Print current line by calling print_a_line function
+print_a_line(current_line, current_file)
+
+# Set current line to 2 by adding 1
+current_line += 1
+# Print current line by calling print_a_line function
+print_a_line(current_line, current_file)
+
+# Set current line to 3 by adding 1
+current_line += 1
+# Print current line by calling print_a_line function
+print_a_line(current_line, current_file)
diff --git a/Python3/ex20.py b/Python3/ex20.py
index 701c6eb..48abb39 100755
--- a/Python3/ex20.py
+++ b/Python3/ex20.py
@@ -1,68 +1,37 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex20: Functions and Files
 
-# Import argv variables from the sys module
 from sys import argv
 
-# Assign the first and the second arguments to the two variables
 script, input_file = argv
 
-
-# Define a function called print_call to print the whole contents of a
-# file, with one file object as formal parameter
 def print_all(f):
-    # print the file contents
     print(f.read())
 
-
-# Define a function called rewind to make the file reader go back to
-# the first byte of the file, with one file object as formal parameter
 def rewind(f):
-    # make the file reader go back to the first byte of the file
     f.seek(0)
 
-
-# Define a function called print_a_line to print a line of the file,
-# with a integer counter and a file object as formal parameters
 def print_a_line(line_count, f):
-    # Test whether two variables are carrying the same value
-    print("line_count equal to current_line?:", (line_count == current_line))
-    # print the number and the contents of a line
     print(line_count, f.readline())
 
-
-# Open a file
 current_file = open(input_file)
 
-# Print "First let's print the whole file:"
 print("First let's print the whole file:\n")
 
-# call the print_all function to print the whole file
 print_all(current_file)
 
-# Print "Now let's rewind, kind of like a tape."
 print("Now let's rewind, kind of like a tape.")
 
-# Call the rewind function to go back to the beginning of the file
 rewind(current_file)
 
-# Now print three lines from the top of the file
-
-# Print "Let's print three lines:"
 print("Let's print three lines:")
 
-# Set current line to 1
 current_line = 1
-# Print current line by calling print_a_line function
 print_a_line(current_line, current_file)
 
-# Set current line to 2 by adding 1
-current_line += 1
-# Print current line by calling print_a_line function
+current_line = current_line + 1
 print_a_line(current_line, current_file)
 
-# Set current line to 3 by adding 1
-current_line += 1
-# Print current line by calling print_a_line function
-print_a_line(current_line, current_file)
+current_line = current_line + 1
+print_a_line(current_line, current_file)
\ No newline at end of file
diff --git a/Python3/ex21-studydrills.py b/Python3/ex21-studydrills.py
new file mode 100644
index 0000000..7495cce
--- /dev/null
+++ b/Python3/ex21-studydrills.py
@@ -0,0 +1,62 @@
+#!/usr/bin/env python3
+
+# ex21: Functions Can Return Something
+
+def add(a, b):
+    print("ADDING %d + %d" % (a, b))
+    return a + b
+
+def subtract(a, b):
+    print("SUBTRACTING %d - %d" % (a, b))
+    return a - b
+
+def multiply(a, b):
+    print("MULTIPLYING %d * %d" % (a, b))
+    return a * b
+
+def divide(a, b):
+    print("DIVIDING %d / %d" % (a, b))
+    return a / b
+
+# my function to test return
+def isequal(a, b):
+    print("Is %r equal to %r? - " % (a, b), end="")
+    return (a == b)
+
+print("Let's do some math with just functions!")
+
+age = add(30, 5)
+height = subtract(78, 4)
+weight = multiply(92, 2)
+iq = divide(100, 2)
+
+print("Age: %d, Height: %d, Weight: %d, IQ: %d" % (age, height, weight, iq))
+
+
+# A puzzle for the extra credit, type it in anyway.
+print("Here is a puzzle.")
+
+# switch the order of multiply and divide
+what = add(age, subtract(height, divide(weight, multiply(iq, 2))))
+
+print("That becomes: ", what, "Can you do it by hand?")
+
+# test the return value of isequal()
+num1 = 40
+num2 = 50
+num3 = 50
+
+print(isequal(num1, num2))
+print(isequal(num2, num3))
+
+
+# A new puzzle.
+print("Here is a new puzzle.")
+
+# write a simple formula and use the function again
+uplen = 50
+downlen = 100
+height = 80
+what_again = divide(multiply(height, add(uplen, downlen)), 2)
+
+print("That become: ", what_again, "Bazinga!")
\ No newline at end of file
diff --git a/Python3/ex21.py b/Python3/ex21.py
index 16f3828..a7f8c2f 100755
--- a/Python3/ex21.py
+++ b/Python3/ex21.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex21: Functions Can Return Something
 
@@ -6,28 +6,18 @@ def add(a, b):
     print("ADDING %d + %d" % (a, b))
     return a + b
 
-
 def subtract(a, b):
     print("SUBTRACTING %d - %d" % (a, b))
     return a - b
 
-
 def multiply(a, b):
     print("MULTIPLYING %d * %d" % (a, b))
     return a * b
 
-
 def divide(a, b):
     print("DIVIDING %d / %d" % (a, b))
     return a / b
 
-
-# my function to test return
-def isequal(a, b):
-    print("Is %r equal to %r? - " % (a, b), end="")
-    return (a == b)
-
-
 print("Let's do some math with just functions!")
 
 age = add(30, 5)
@@ -41,28 +31,6 @@ def isequal(a, b):
 # A puzzle for the extra credit, type it in anyway.
 print("Here is a puzzle.")
 
-# switch the order of multiply and divide
 what = add(age, subtract(height, divide(weight, multiply(iq, 2))))
 
-print("That becomes: ", what, "Can you do it by hand?")
-
-
-# test the return value of isequal()
-num1 = 40
-num2 = 50
-num3 = 50
-
-print(isequal(num1, num2))
-print(isequal(num2, num3))
-
-
-# A new puzzle.
-print("Here is a new puzzle.")
-
-# write a simple formula and use the function again
-uplen = 50
-downlen = 100
-height = 80
-what_again = divide(multiply(height, add(uplen, downlen)), 2)
-
-print("That become: ", what_again, "Bazinga!")
+print("That becomes: ", what, "Can you do it by hand?")
\ No newline at end of file
diff --git a/Python3/ex24-studydrills.py b/Python3/ex24-studydrills.py
new file mode 100644
index 0000000..34b1497
--- /dev/null
+++ b/Python3/ex24-studydrills.py
@@ -0,0 +1,43 @@
+#!/usr/bin/env python3
+
+# ex24: More Practice
+
+print("Let's practice everything.")
+print("You\'d need to know \'bout escapes with \\ that do \n newlines and \t tabs.")
+
+poem = """
+\t The lovely world
+with logic so firmly planted
+cannot discern \n the needs of love
+nor comprehend passion from intuition
+and requires an explanation
+\n\t\twhere there is none.
+"""
+
+print("--------------------")
+print(poem)
+print("--------------------")
+
+
+five = 10 - 2 + 3 - 6
+print("This should be five: %s" % five)
+
+def secret_formala(started):
+    jelly_beans = started * 500
+    jars = jelly_beans / 1000
+    crates = jars / 100
+    return jelly_beans, jars, crates
+
+
+start_point = 1000
+beans, jars, crates = secret_formala(start_point)
+
+print("With a starting point of: %d" % start_point)
+# use the tuple as the parameters for the formatter
+print("We'd have %d beans, %d jars, and %d crates." % (beans, jars, crates))
+
+start_point = start_point / 10
+
+print("We can also do that this way:")
+# call the function and use its return values as the parameters for the formatter
+print("We'd have %d beans, %d jars, and %d crates." % secret_formala(start_point))
diff --git a/Python3/ex24.py b/Python3/ex24.py
index 0ee67e9..e39c85a 100755
--- a/Python3/ex24.py
+++ b/Python3/ex24.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex24: More Practice
 
@@ -22,7 +22,6 @@
 five = 10 - 2 + 3 - 6
 print("This should be five: %s" % five)
 
-
 def secret_formala(started):
     jelly_beans = started * 500
     jars = jelly_beans / 1000
@@ -34,11 +33,9 @@ def secret_formala(started):
 beans, jars, crates = secret_formala(start_point)
 
 print("With a starting point of: %d" % start_point)
-# use the tuple as the parameters for the formatter
 print("We'd have %d beans, %d jars, and %d crates." % (beans, jars, crates))
 
 start_point = start_point / 10
 
 print("We can also do that this way:")
-# call the function and use its return values as the parameters for the formatter
 print("We'd have %d beans, %d jars, and %d crates." % secret_formala(start_point))
diff --git a/Python3/ex25.py b/Python3/ex25.py
index 8a954f0..6862505 100755
--- a/Python3/ex25.py
+++ b/Python3/ex25.py
@@ -1,46 +1,39 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex: even more practice
 
-
 def break_words(stuff):
     """ This function will break up words for us. """
     words = stuff.split(' ')
     return words
 
-
 def sort_words(words):
     """ Sorts the words. """
     return sorted(words)
 
-
 def print_first_word(words):
     """ Prints the first word after popping it off. """
     word = words.pop(0)
     print(word)
 
-
 def print_last_word(words):
     """ Prints the last word after popping it off. """
     word = words.pop(-1)
     print(word)
 
-
 def sort_sentence(sentence):
     """ Takes in a full sentence and returns the sorted words. """
     words = break_words(sentence)
     return sort_words(words)
 
-
 def print_first_and_last(senence):
     """ Prints the first and last words of the sentences. """
     words = break_words(senence)
     print_first_word(words)
     print_last_word(words)
 
-
 def print_first_and_last_sorted(sentence):
     """ Sorts the words then prints the first and last one. """
     words = sort_sentence(sentence)
     print_first_word(words)
-    print_last_word(words)
+    print_last_word(words)
\ No newline at end of file
diff --git a/Python3/ex26.py b/Python3/ex26.py
index b7f889c..f05886c 100755
--- a/Python3/ex26.py
+++ b/Python3/ex26.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 def break_words(stuff):
     """This function will break up words for us."""
@@ -116,4 +116,4 @@ def secret_formula(started):
 print_first_and_last(sentence)
 
 # bug:   print_first_a_last_sorted(senence)
-print_first_and_last_sorted(sentence)
+print_first_and_last_sorted(sentence)
\ No newline at end of file
diff --git a/Python3/ex29-studydrills.py b/Python3/ex29-studydrills.py
new file mode 100644
index 0000000..0331fc2
--- /dev/null
+++ b/Python3/ex29-studydrills.py
@@ -0,0 +1,44 @@
+#!/usr/bin/env python3
+
+# ex29: What If
+
+people = 20
+cats = 30
+dogs = 15
+
+if people < cats:
+    print("Too many cats! The world is doomed!")
+
+if people > cats:
+    print("Not many cats! The world is saved!")
+
+if people < dogs:
+    print("The world is drooled on!")
+
+if people > dogs:
+    print("The world is dry!")
+
+dogs += 5
+
+if people >= dogs:
+    print("People are greater than or equal to dogs.")
+
+if people <= dogs:
+    print("People are less than or equal to dogs.")
+
+if people == dogs:
+    print("People are dogs.")
+
+dogs += 5
+
+if (dogs < cats) and (people < cats):
+    print("Cats are more than people and dogs. People are scared by cats!")    
+
+if (dogs < cats) and not (people < cats):
+    print("Cats are more than dogs. Mice are living a hard life!")
+    
+if (dogs == cats) or (cats < 10):
+    print("Cats are fighting against dogs! Mice are happy!")
+
+if cat != 0: 
+    print("Cats are still exist. Mice cannot be too crazy.")  
\ No newline at end of file
diff --git a/Python3/ex29.py b/Python3/ex29.py
index a4a6297..7474564 100755
--- a/Python3/ex29.py
+++ b/Python3/ex29.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex29: What If
 
@@ -6,7 +6,6 @@
 cats = 30
 dogs = 15
 
-
 if people < cats:
     print("Too many cats! The world is doomed!")
 
@@ -28,27 +27,4 @@
     print("People are less than or equal to dogs.")
 
 if people == dogs:
-    print("People are dogs.")
-
-dogs += 5
-
-if people >= dogs:
-    print("People are greater than or equal to dogs.")
-
-if people <= dogs:
-    print("People are less than or equal to dogs.")
-
-if people == dogs:
-    print("People are dogs.")
-
-if (dogs < cats) and (people < cats):
-    print("Cats are more than people and dogs. People are scared by cats!")    
-
-if (dogs < cats) and not (people < cats):
-    print("Cats are more than dogs. Mice are living a hard life!")
-    
-if (dogs == cats) or (cats < 10):
-    print("Cats are fighting against dogs! Mice are happy!")
-
-if cat != 0: 
-    print("Cats are still exist. Mice cannot be too crazy.")  
+    print("People are dogs.")
\ No newline at end of file
diff --git a/Python3/ex30-studydrills.py b/Python3/ex30-studydrills.py
new file mode 100644
index 0000000..a59ba71
--- /dev/null
+++ b/Python3/ex30-studydrills.py
@@ -0,0 +1,61 @@
+#!/usr/bin/env python3
+
+# ex30: Else and If
+
+# assign 30 to variable people
+people = 30
+# assign 40 to variable cars
+cars = 40
+# assign 15 to variable buses
+buses = 15
+
+# if cars are more than people
+if cars > people:
+    # print "We should take the cars."
+    print("We should take the cars.")
+# if cars are less than people
+elif cars < people:
+    # print "We should not take the cars"
+    print("We should not take the cars")
+# if cars are equal to people
+else:
+    print("We can't decide.")
+
+# if buses are more than cars    
+if buses > cars:
+    # print "That's too many buses."
+    print("That's too many buses.")
+# if buses are less than cars    
+elif buses < cars:
+    # print "Maybe we could take the buses."
+    print("Maybe we could take the buses.")
+# if buses are equal to cars    
+else:
+    # print "We still can't decide."
+    print("We still can't decide.")
+
+# if people are more than buses
+if people > buses:
+    # print "Alright, let's just take the buses."
+    print("Alright, let's just take the buses.")
+# if people are less than buses
+else:
+    # print "Fine, let's stay home then."
+    print("Fine, let's stay home then.")
+
+# if people are more than cars but less than buses
+if people > cars and people < buses:
+    # print "There are many Busses but few cars."
+    print("There are many Busses but few cars.")
+# if people are less than cars but more than buses
+elif people < cars and people > buses:
+    # print "There are many cars but few busses."
+    print("There are many cars but few busses.")
+# if people are more than cars and buses
+elif people > cars and people > buses:
+    # print "There are few busses and cars."
+    print("There are few busses and cars.")
+# if people are less than cars and buses    
+else:
+    # print "There are many busses and cars."
+    print("There are many busses and cars.")
\ No newline at end of file
diff --git a/Python3/ex30.py b/Python3/ex30.py
index 8e06352..3724a3f 100755
--- a/Python3/ex30.py
+++ b/Python3/ex30.py
@@ -1,61 +1,26 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex30: Else and If
 
-# assign 30 to variable people
 people = 30
-# assign 40 to variable cars
 cars = 40
-# assign 15 to variable buses
 buses = 15
 
-# if cars are more than people
 if cars > people:
-    # print "We should take the cars."
     print("We should take the cars.")
-# if cars are less than people
 elif cars < people:
-    # print "We should not take the cars"
     print("We should not take the cars")
-# if cars are equal to people
 else:
     print("We can't decide.")
 
-# if buses are more than cars    
 if buses > cars:
-    # print "That's too many buses."
     print("That's too many buses.")
-# if buses are less than cars    
 elif buses < cars:
-    # print "Maybe we could take the buses."
     print("Maybe we could take the buses.")
-# if buses are equal to cars    
 else:
-    # print "We still can't decide."
     print("We still can't decide.")
 
-# if people are more than buses
 if people > buses:
-    # print "Alright, let's just take the buses."
     print("Alright, let's just take the buses.")
-# if people are less than buses
 else:
-    # print "Fine, let's stay home then."
-    print("Fine, let's stay home then.")
-
-# if people are more than cars but less than buses
-if people > cars and people < buses:
-    # print "There are many Busses but few cars."
-    print("There are many Busses but few cars.")
-# if people are less than cars but more than buses
-elif people < cars and people > buses:
-    # print "There are many cars but few busses."
-    print("There are many cars but few busses.")
-# if people are more than cars and buses
-elif people > cars and people > buses:
-    # print "There are few busses and cars."
-    print("There are few busses and cars.")
-# if people are less than cars and buses    
-else:
-    # print "There are many busses and cars."
-    print("There are many busses and cars.")
+    print("Fine, let's stay home then.")
\ No newline at end of file
diff --git a/Python3/ex31-studydrills.py b/Python3/ex31-studydrills.py
new file mode 100644
index 0000000..ffd70cf
--- /dev/null
+++ b/Python3/ex31-studydrills.py
@@ -0,0 +1,52 @@
+#!/usr/bin/env python3
+
+# ex31: Making Decisions
+
+print("You enter a dark room with two doors. Do you go through door #1 or door #2?")
+
+door = input("> ")
+
+if door == "1":
+    print("There's a giant bear here eating a cheese cake. What do you do?")
+    print("1. Take the cake.")
+    print("2. Scream at the bear.")
+
+    bear = input("> ")
+
+    if bear == "1":
+        print("The bear eats your face off. Good job!")
+    elif bear == "2":
+        print("The bear eats your legs off. Good job!")
+    else:
+        print("Well, doing %s is probably better. Bear runs away." % bear)
+
+elif door == "2":
+    print("You stare into the endless abyss at Cthulhu's retina.")
+    print("1. Blueberries.")
+    print("2. Yellow jacket clothespins.")
+    print("3. Understanding revolvers yelling melodies.")
+
+    insanity = input("> ")
+
+    if insanity == "1" or insanity == "2":
+        print("Your body survives powered by a mind of jello. Good job!")
+    else:
+        print("The insanity rots you ")
+
+elif door == "3":
+    print("You are asked to select one pill from two and take it. One is red, and the other is blue.")
+    print("1. take the red one.")
+    print("2. take the blue one.")
+
+    pill = input("> ")
+
+    if pill == "1":
+        print("You wake up and found this is just a ridiculous dream. Good job!")
+    elif pill == "2":
+        print("It's poisonous and you died.")
+    else:
+        print("The man got mad and killed you.")
+
+else:
+    print("You wake up and found this is just a ridiculous dream.")
+    print("However you feel a great pity haven't entered any room and found out what it will happens!")
\ No newline at end of file
diff --git a/Python3/ex31.py b/Python3/ex31.py
index 60ffc6a..0189cad 100755
--- a/Python3/ex31.py
+++ b/Python3/ex31.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex31: Making Decisions
 
@@ -18,36 +18,20 @@
     elif bear == "2":
         print("The bear eats your legs off. Good job!")
     else:
-        print("Well, doing %s is probably better. Bear runs away." % bear)
-
+        print("Well, doing {} is probably better. Bear runs away.".format(bear))
+    
 elif door == "2":
     print("You stare into the endless abyss at Cthulhu's retina.")
     print("1. Blueberries.")
     print("2. Yellow jacket clothespins.")
     print("3. Understanding revolvers yelling melodies.")
-
+    
     insanity = input("> ")
-
+    
     if insanity == "1" or insanity == "2":
-        print("Your body survives powered by a mind of jello. Good job!")
-    else:
-        print("The insanity rots you ")
-
-elif door == "3":
-    print("You are asked to select one pill from two and take it. One is red, and the other is blue.")
-    print("1. take the red one.")
-    print("2. take the blue one.")
-
-    pill = input("> ")
-
-    if pill == "1":
-        print("You wake up and found this is just a ridiculous dream. Good job!")
-    elif pill == "2":
-        print("It's poisonous and you died.")
+        print("Your body survives powered by a mind of a jello. good job!")
     else:
-        print("The man got mad and killed you.")
-
+        print("The insanity roots your eyes into a pool of muck. Good job!")
 
 else:
-    print("You wake up and found this is just a ridiculous dream.")
-    print("However you feel a great pity haven't entered any room and found out what it will happens!")
+    print("You stumble around and fall on a knife and die. Good job!")
\ No newline at end of file
diff --git a/Python3/ex32.py b/Python3/ex32.py
index d655bee..c4b3bef 100755
--- a/Python3/ex32.py
+++ b/Python3/ex32.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex32: Loops and Lists
 
@@ -10,12 +10,10 @@
 for number in the_count:
     print("This is count %d" % number)
 
-
 # same as above
 for fruit in fruits:
     print("A fruit of type: %s" % fruit)
 
-
 # also we can go through mixed lists too
 # notice we have to use %r since we don't know what's in it
 for i in change:
@@ -29,4 +27,4 @@
     
 # now we can print them out too
 for i in elements:
-    print("Element was: %d" % i)
+    print("Element was: %d" % i)
\ No newline at end of file
diff --git a/Python3/ex33-studydrills.py b/Python3/ex33-studydrills.py
new file mode 100644
index 0000000..70641eb
--- /dev/null
+++ b/Python3/ex33-studydrills.py
@@ -0,0 +1,21 @@
+#!/usr/bin/env python3
+
+# ex33: While Loops
+
+def createNumbers(max, step):
+    i = 0
+    numbers = []
+    for i in range(0, max, step):
+        print("At the top i is %d" % i)
+        numbers.append(i)
+
+        print("Numbers now: ", numbers)
+        print("At the bottom i is %d" % i)
+    return numbers 
+
+numbers = createNumbers(10, 2)
+
+print("The number: ")
+
+for num in numbers:
+    print(num)
\ No newline at end of file
diff --git a/Python3/ex33.py b/Python3/ex33.py
index 7a89ae5..7fc7151 100755
--- a/Python3/ex33.py
+++ b/Python3/ex33.py
@@ -1,21 +1,19 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex33: While Loops
 
-def createNumbers(max, step):
-    i = 0
-    numbers = []
-    for i in range(0, max, step):
-        print("At the top i is %d" % i)
-        numbers.append(i)
+i = 0
+numbers = []
 
-        print("Numbers now: ", numbers)
-        print("At the bottom i is %d" % i)
-    return numbers 
+while i < 6:
+    print("At the top i is {}".format(i))
+    numbers.append(i)
+    
+    i = i + 1
+    print("Numbers now: ", numbers)
+    print("At the bottom i is {}".format(i))
 
-numbers = createNumbers(10, 2)
-
-print("The number: ")
+print("The numbers:")
 
 for num in numbers:
-    print(num)
+    print(num)
\ No newline at end of file
diff --git a/Python3/ex34.py b/Python3/ex34.py
index d7b1b01..45e02e9 100755
--- a/Python3/ex34.py
+++ b/Python3/ex34.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex34: Accessing Elements of Lists
 
@@ -17,4 +17,4 @@ def printAnimal(index):
     print("The animal at %d is the %s animal and is a %s" % (index-1, num2en, animals[index-1]))
 
 for i in range(1, 7):
-    printAnimal(i)
+    printAnimal(i)
\ No newline at end of file
diff --git a/Python3/ex35.py b/Python3/ex35.py
index fb24860..18f1615 100755
--- a/Python3/ex35.py
+++ b/Python3/ex35.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex35: Branches and Functions
 
@@ -82,5 +82,4 @@ def start():
     else:
         dead("You stumble around the room until you starve.")
 
-
-start()
+start()
\ No newline at end of file
diff --git a/Python3/ex37.py b/Python3/ex37.py
index ad53056..56513fe 100755
--- a/Python3/ex37.py
+++ b/Python3/ex37.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex37: Symbol Review
 
@@ -221,4 +221,4 @@ def makeDouble():
 num_list = [5, 10, 15, 'hello']
 print('\nNow we multiples each elements in num_list with 2:')
 for num in num_list:
-    print(adder(num))
+    print(adder(num))
\ No newline at end of file
diff --git a/Python3/ex38.py b/Python3/ex38.py
index e3e17e8..056d62f 100755
--- a/Python3/ex38.py
+++ b/Python3/ex38.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex38: Doing Things To Lists
 
@@ -23,4 +23,4 @@
 print(stuff[-1])  # whoa! fancy
 print(stuff.pop())
 print(' '.join(stuff))  # what? cool!
-print('#'.join(stuff[3:5]))  # super stellar!
+print('#'.join(stuff[3:5]))  # super stellar!
\ No newline at end of file
diff --git a/Python3/ex39-studydrills.py b/Python3/ex39-studydrills.py
new file mode 100644
index 0000000..d0c33c0
--- /dev/null
+++ b/Python3/ex39-studydrills.py
@@ -0,0 +1,94 @@
+#!/bin/python3
+
+# ex39: Dictionaries, Oh Lovely Dictionaries
+
+# create a mapping of state to abbreviation
+states = {
+    'Oregon': 'OR',
+    'Florida': 'FL',
+    'California': 'CA',
+    'New York': 'NY',
+    'Michigan': 'MI'
+}
+
+# create a basic set of states and some cities in them
+cities = {
+    'CA': 'San Fransisco',
+    'MI': 'Detroit',
+    'FL': 'Jacksonville'
+    }
+
+# add some more cities
+cities['NY'] = 'New York'
+cities['OR'] = 'Portland'
+
+# print out some cities
+print('-' * 10)
+print("NY State has: ", cities['NY'])
+print('OR State has: ', cities['OR'])
+
+# do it by using the state then cities dict
+print('-' * 10)
+print("Michigan has: ", cities[states['Michigan']])
+print("Florida has:", cities[states['Florida']])
+
+# print every state abbreviation
+print('-' * 10)
+for state, abbrev in states.items():
+    print("%s is abbreviated %s" % (state, abbrev))
+
+# print every city in state
+print('-' * 10)
+for abbrev, city in cities.items():
+    print("%s has the city %s" % (abbrev, city))
+
+# now do both at the same time
+print('-' * 10)
+for state, abbrev in states.items():
+    print("%s state is abbreviated %s and has city %s" % (
+        states, abbrev, cities[abbrev]))
+
+print('-' * 10)
+# safely get a abbreviation by state that might not be there
+state = states.get('Texas', None)
+
+if not state:
+    print("Sorry, no Texas.")
+
+# get a city with a default value
+city = cities.get("TX", 'Does Not Exist')
+print("The city for the state 'TX' is %s" % city)
+
+# create a mapping of province to abbreviation
+cn_province = {
+    '广东': '粤',
+    '湖南': '湘',
+    '四川': '川',
+    '云南': '滇',
+    }
+
+# create a basic set of provinces and some cities in them
+cn_cities = {
+    '粤': '广州',
+    '湘': '长沙',
+    '川': '成都',
+    }
+
+# add some more data
+cn_province['台湾'] = '台'
+
+cn_cities['滇'] = '昆明'
+cn_cities['台'] = '高雄'
+
+print('-' * 10)
+for prov, abbr in cn_province.items():
+    print("%s省的缩写是%s" % (prov, abbr))
+
+print('-' * 10)
+cn_abbrevs = {values: keys for keys, values in cn_province.items()}
+for abbrev, prov in cn_abbrevs.items():
+    print("%s是%s省的缩写" % (abbrev, prov))
+
+print('-' * 10)
+for abbrev, city in cn_cities.items():
+    print("%s市位于我国的%s省" % (city, cn_abbrevs[abbrev]))
diff --git a/Python3/ex39.py b/Python3/ex39.py
index d0c33c0..88c851a 100755
--- a/Python3/ex39.py
+++ b/Python3/ex39.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex39: Dictionaries, Oh Lovely Dictionaries
 
@@ -57,38 +57,4 @@
 
 # get a city with a default value
 city = cities.get("TX", 'Does Not Exist')
-print("The city for the state 'TX' is %s" % city)
-
-# create a mapping of province to abbreviation
-cn_province = {
-    '广东': '粤',
-    '湖南': '湘',
-    '四川': '川',
-    '云南': '滇',
-    }
-
-# create a basic set of provinces and some cities in them
-cn_cities = {
-    '粤': '广州',
-    '湘': '长沙',
-    '川': '成都',
-    }
-
-# add some more data
-cn_province['台湾'] = '台'
-
-cn_cities['滇'] = '昆明'
-cn_cities['台'] = '高雄'
-
-print('-' * 10)
-for prov, abbr in cn_province.items():
-    print("%s省的缩写是%s" % (prov, abbr))
-
-print('-' * 10)
-cn_abbrevs = {values: keys for keys, values in cn_province.items()}
-for abbrev, prov in cn_abbrevs.items():
-    print("%s是%s省的缩写" % (abbrev, prov))
-
-print('-' * 10)
-for abbrev, city in cn_cities.items():
-    print("%s市位于我国的%s省" % (city, cn_abbrevs[abbrev]))
+print("The city for the state 'TX' is %s" % city)
\ No newline at end of file
diff --git a/Python3/ex40-studydrills.py b/Python3/ex40-studydrills.py
new file mode 100644
index 0000000..568a0e3
--- /dev/null
+++ b/Python3/ex40-studydrills.py
@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+
+# ex40: Modules, CLasses, and Objects
+
+class Song(object):
+
+    def __init__(self, disk):
+        self.index = 0
+        self.disk = disk
+        self.jump()
+
+    def next(self):
+        ''' next song. '''
+        self.index = (self.index + 1) % len(self.disk)
+        self.jump()
+
+    def prev(self):
+        ''' prev song. '''
+        self.index = (self.index - 1) % len(self.disk)
+        self.jump()
+            
+    def jump(self):
+        ''' jump to the song. '''
+        self.lyrics = self.disk[self.index]
+
+    def sing_me_a_song(self):
+        for line in self.lyrics:
+            print(line)
+
+# construct a disk      
+song1 =  ["Happy birthday to you",
+"I don't want to get sued",
+"So I'll stop right there"]           
+
+song2 = ["They rally around the family",
+"With pockets full of shells"
+]
+
+song3 = ["Never mind I find",
+"Some one like you"
+]
+
+disk = [song1, song2, song3]
+
+mycd = Song(disk)
+mycd.sing_me_a_song()
+
+mycd.next()
+mycd.sing_me_a_song()
+
+mycd.next()
+mycd.sing_me_a_song()
+
+mycd.next()
+mycd.sing_me_a_song()
+
+mycd.prev()
+mycd.sing_me_a_song()
+
+mycd.prev()
+mycd.sing_me_a_song()
+
+mycd.prev()
+mycd.sing_me_a_song()
+
+mycd.prev()
+mycd.sing_me_a_song()
\ No newline at end of file
diff --git a/Python3/ex40.py b/Python3/ex40.py
index e1fb253..9df7882 100755
--- a/Python3/ex40.py
+++ b/Python3/ex40.py
@@ -1,65 +1,23 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
-class Song(object):
-
-    def __init__(self, disk):
-        self.index = 0
-        self.disk = disk
-        self.jump()
-
-    def next(self):
-        ''' next song. '''
-        self.index = (self.index + 1) % len(self.disk)
-        self.jump()
-
-    def prev(self):
-        ''' prev song. '''
-        self.index = (self.index - 1) % len(self.disk)
-        self.jump()
-            
-    def jump(self):
-        ''' jump to the song. '''
-        self.lyrics = self.disk[self.index]
+# ex40: Modules, CLasses, and Objects
 
+class Song(object):
+    
+    def __init__(self,lyrics):
+        self.lyrics = lyrics
+    
     def sing_me_a_song(self):
         for line in self.lyrics:
             print(line)
 
-# construct a disk      
-song1 =  ["Happy birthday to you",
-"I don't want to get sued",
-"So I'll stop right there"]           
-
-song2 = ["They rally around the family",
-"With pockets full of shells"
-]
-
-song3 = ["Never mind I find",
-"Some one like you"
-]
-
-disk = [song1, song2, song3]
-
-mycd = Song(disk)
-mycd.sing_me_a_song()
-
-mycd.next()
-mycd.sing_me_a_song()
-
-mycd.next()
-mycd.sing_me_a_song()
-
-mycd.next()
-mycd.sing_me_a_song()
-
-mycd.prev()
-mycd.sing_me_a_song()
+happy_bday = Song(["Happy birthday to you",
+                   "I don't want to get sued",
+                   "So I'll stop right there"])
 
-mycd.prev()
-mycd.sing_me_a_song()
+bulls_on_parade = Song(["They rally around the family",
+                        "With pockets full of shells"])
 
-mycd.prev()
-mycd.sing_me_a_song()
+happy_bday.sing_me_a_song()
 
-mycd.prev()
-mycd.sing_me_a_song()
+bulls_on_parade.sing_me_a_song()
\ No newline at end of file
diff --git a/Python3/ex41.py b/Python3/ex41.py
index 30ad6ba..0e57a80 100755
--- a/Python3/ex41.py
+++ b/Python3/ex41.py
@@ -1,4 +1,4 @@
-#!/bin/python3
+#!/usr/bin/env python3
 
 # ex41: Learning To Speak Object Oriented
 
@@ -31,12 +31,10 @@
 
 # load up the words from the website
 for word in urlopen(WORD_URL).readlines():
-    WORDS.append(word.strip())
-
+    WORDS.append(word.strip().decode("utf-8"))
 
 def convert(snippet, phrase):
-    class_names = [w.capitalize() for w in
-                   random.sample(WORDS, snippet.count("%%%"))]
+    class_names = [w.capitalize() for w in random.sample(WORDS, snippet.count("%%%"))]
     other_names = random.sample(WORDS, snippet.count("***"))
     results = []
     param_names = []
@@ -64,7 +62,6 @@ def convert(snippet, phrase):
 
     return results
 
-
 # keep going until they hit CTRL-D
 try:
     while True:
@@ -82,4 +79,4 @@ def convert(snippet, phrase):
             input("> ")
             print("ANSWER:  %s\n\n" % answer)
 except EOFError:
-    print("\nBye")
+    print("\nBye")
\ No newline at end of file