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.

She's a dumb SLUT, really,
but a lid for every pot.
Game of Thrones Season 2, Episode 1

The SLUT cannot pay for all of this.
Game of Thrones Season 3, Episode 3

- Whore! Sinner!
- Slut!
Game of Thrones Season 5, Episode 10

So, you need to look like
a street... SLUT.
Money Heist Season 1, Episode 9

- What a SLUT!
- Traitor!
Game of Thrones Season 7, Episode 3