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.

Sorry.
I'm just trying to CHEER my buddy up.
The Big Bang Theory Season 4, Episode 23

If you didn't CHEER at my entrance,
it's too late to buy into the premise.
The Big Bang Theory Season 3, Episode 4

Really hoping
this will CHEER him up.
The Big Bang Theory Season 7, Episode 22

Don't CHEER too loud.
Game of Thrones Season 4, Episode 9

Cheer up, Lord Edmure.
Game of Thrones Season 6, Episode 6