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.

See, Papa Doc's capital idea,
that's Port-Au-Prince.
The Big Bang Theory Season 1, Episode 1

Come on, PAPA needs
to void his bladder.
The Big Bang Theory Season 5, Episode 4

Your PAPA was mean to you.
Game of Thrones Season 7, Episode 7

and your dead PAPA.
Game of Thrones Season 4, Episode 3

Papa!
Westworld Season 2, Episode 4