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.

If that Aquaman feels wet,
it's not a GIMMICK.
The Big Bang Theory Season 12, Episode 14

Yeah, right. That's the GIMMICK.
What GIMMICK?
Breaking Bad Season 4, Episode 2

Yeah, right. That's the GIMMICK.
What GIMMICK?
Breaking Bad Season 4, Episode 2