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.

Huh? Was the SACK
of Rome a game?
The Big Bang Theory Season 5, Episode 1

But a sinner in the SACK.
The Big Bang Theory Season 9, Episode 17

You lying SACK of shit.
Game of Thrones Season 5, Episode 7

You lying,
two-faced SACK of shit.
Breaking Bad Season 5, Episode 9

You know, there was a time I would say,
"What's a soup SACK?"
The Big Bang Theory Season 10, Episode 20