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.

You're a proper LOVER, Jon Snow.
Game of Thrones Season 3, Episode 6

I happen to be a giving
and generous LOVER.
The Big Bang Theory Season 9, Episode 9

In the relationships of love,
we have the LOVER and the beloved.
Money Heist Season 3, Episode 5

"We’ve always heard stories about husbands
catching their wives with their LOVER.
Money Heist Season 1, Episode 12

I never figured you
for a moose LOVER,
Breaking Bad Season 5, Episode 11