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.

- On occasion, yeah.
- Owner's a big BOOSTER for the DEA.
Breaking Bad Season 3, Episode 8

how I can fit
in the BOOSTER seats.
The Big Bang Theory Season 5, Episode 4

Well, like you said, he's a-- This man
is a big law enforcement BOOSTER.
Breaking Bad Season 4, Episode 8