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.

But I didn't SPOIL anything.
The Big Bang Theory Season 2, Episode 22

But someone might SPOIL the movie.
The Big Bang Theory Season 9, Episode 11

You're gonna SPOIL him.
Breaking Bad Season 5, Episode 15

Won't that SPOIL our appetites
The Big Bang Theory Season 5, Episode 6

It doesn't SPOIL...
The Big Bang Theory Season 1, Episode 4