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 almost feel sorry for the poor FOOL
sitting in his split-level suburban ranch...
The Big Bang Theory Season 4, Episode 19

you're a bloody FOOL.
Game of Thrones Season 6, Episode 8

King Robert is FOOL enough
to meet them in open battle,
Game of Thrones Season 1, Episode 4

Don’t let them FOOL you."
Money Heist Season 1, Episode 11

And I'm sure some FOOL
in the Donner party
The Big Bang Theory Season 5, Episode 15