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.

♪ Making it
much harder to CRACK ♪
The Big Bang Theory Season 7, Episode 6

I could grab my rifle, CRACK your skull,
leave you fucked...
Money Heist Season 3, Episode 5

was CRACK skulls and fuck girls.
Game of Thrones Season 1, Episode 1

(BONES CRACK)
Westworld Season 3, Episode 8

Crack him over the head
with something?
Breaking Bad Season 2, Episode 2