Fix grammar

src/arrays/challenges.md

@@ -13,7 +13,7 @@ Edit the following program so that the output is zero.
 void main() {
     // Only change this line
     String[] words = { "Sam", "I", "Am" };
-    System.out.println(array.length);
+    IO.println(words.length);
 }
 ```
 

src/arrays/reassignment.md

@@ -20,7 +20,7 @@ System.out.println(numbers.length);
 ~}
 ```
 
-This reassignment will not be affect any variables which
+This reassignment will not affect any variables which
 are aliases for the variable's old value.
 
 ```java

src/arrays/relation_to_final_variables.md

@@ -12,7 +12,7 @@ final char[] catchphrase = { 'w', 'o', 'a', 'h', '!' };
 System.out.println(catchphrase);
 
 // Cannot reassign
-// catchphrase = { 'e', 'g', 'a', 'd', 's' }
+// catchphrase = new char[] { 'e', 'g', 'a', 'd', 's' }
 // but can set elements directly
 catchphrase[0] = 'e';
 catchphrase[1] = 'g';

src/loops_ii/comparison_to_while.md

@@ -54,7 +54,7 @@ while (index < numbers.length) {
 ~}
 ```
 
-Us humans, with our tiny monkey brains, can get very lost when things that are related to eachother are separated
+Us humans, with our tiny monkey brains, can get very lost when things that are related to each other are separated
 by long distances.
 
 In this dimension, for loops are superior. All the bits of code that "control the loop" can be right at the top.