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.

My company's testing
a new STEROID
The Big Bang Theory Season 5, Episode 17

Can I interest you in a topical STEROID
from my lotion and unguent collection?
The Big Bang Theory Season 4, Episode 6