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.

- I'm telling you the Crown is six million in DEBT.
- How could you let this happen?
Game of Thrones Season 1, Episode 3

...but you did secure
a formal acknowledgment of the DEBT.
The Big Bang Theory Season 2, Episode 14

Keep it and consider the DEBT paid.
Game of Thrones Season 3, Episode 7

has ever had a DEBT of this magnitude
repaid in a single installment.
Game of Thrones Season 7, Episode 4

I, on the other hand,
feel you should honor your DEBT.
The Big Bang Theory Season 2, Episode 14