Fix grammar in CONTRIBUTING.md

I hope someone will look further into my editing, in case I missed anything.

CONTRIBUTING.md

@@ -1,18 +1,18 @@
 # Contribution guide
 
-Welcome your contribution. :heart:
+Welcome to your first contribution. :heart:
 
 #### Table Of Contents
 - [Code of Conduct](#code-of-conduct)
 - [Translation Guide](#translation-guide)
 
 ## Code of Conduct
-If you want to contribute, you will need to know a few things.
+If you want to contribute, you need to know a few things.
 
 [Code of conduct](CODE_OF_CONDUCT.md)
 
 ## Translation Guide
-We have the some of rules for translation. If you make first translation for your language, you must need to copy all translation link form `English Page` language link section and paste all translation link on `Your language page`. And then `English Page` link and add 'Your language page' link on all of translated page.
+We have some rules for translation. If you make the first translation for your language, you must copy all translation link from `English Page` language link section and paste all translation link on `Your language page`. And then add 'Your language page' link on `English Page` and all of translated page.
 
 #### Example
 
@@ -36,7 +36,7 @@ at `/translations/other_language.md`
 ```
 
 ## TODO
-- [ ] Fixed grammar for contribution Guide
+- [x] Fixed grammar for contribution Guide
 - [ ] Add more example and more guide
 
 Thanks! :heart: