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.

He wants to be one of you. He wants
to join the Brotherhood. Stop them!
Game of Thrones Season 3, Episode 6

- Where is the Brotherhood?
- I don't know.
Game of Thrones Season 2, Episode 4

Led the attack
on the Kingswood Brotherhood.
Game of Thrones Season 4, Episode 1

The Brotherhood Without Banners
is rallying the commoners against us,
Game of Thrones Season 6, Episode 6

I'm going to stay and smith
for the Brotherhood.
Game of Thrones Season 3, Episode 5