The best way to learn proper English is to read news report, and watch news on TV. Watching TV shows is a great way to learn casual English, slang words, understand culture reference and humor. If you have already watched these shows then you may recall the words used in the following dialogs.

Have the INDIGENOUS fauna
accepted you as one of their own?
The Big Bang Theory Season 3, Episode 6

It's INDIGENOUS to Brazil, as is the cocoa
bean from which we get chocolate.
The Big Bang Theory Season 2, Episode 13