Contributing fixup

contributing.md

@@ -1,12 +1,12 @@
 # Send your tip!
 
-For submit a tip, do a PR in our [GitHub repository](https://github.com/Kikobeats/js-mythbusters).
+To submit a tip, create a PR in our [GitHub repository](https://github.com/Kikobeats/js-mythbusters).
 
-Before add your tip take in consideration the following guidelines:
+Before adding your tip take into consideration the following guidelines:
 
 - Add your tip in the correct section. Each different section is a folder (for example [v8-tips](https://github.com/Kikobeats/js-mythbusters/tree/master/v8-tips) or [workflow](https://github.com/Kikobeats/js-mythbusters/tree/master/workflow)).
 - Inside the folder, each file is a tip.
-- If your tip is very similar to a tip that already exists, consider extend the first tip.
+- If your tip is very similar to a tip that already exists, consider extending the first tip.
 - Don't add more than one tip per file.
-- The text that describe the tip have to be concessive and precise.
-- For avoid extend the tip, you can reference other tips of the site.
+- The text that describes the tip has to be concise and precise.
+- To avoid extending tips till they are too big, you can reference other tips instead.