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.

We can overthrow an EMPIRE.
Game of Thrones Season 6, Episode 2

Hank has been building
a meth EMPIRE
Breaking Bad Season 5, Episode 11

What I mean--
Was it right to run a drug EMPIRE?
Breaking Bad Season 5, Episode 11

It's great to be in the Empire today
The Big Bang Theory Season 6, Episode 6

You know, when I first read the
script for Empire Strikes Back
The Big Bang Theory Season 7, Episode 14