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.

A morally AMBIGUOUS confidence man
who smokes, has lung cancer...
The Big Bang Theory Season 2, Episode 20

- That sounds fair.
- Hold on. Bimonthly is an AMBIGUOUS term.
The Big Bang Theory Season 1, Episode 14

Nothing's AMBIGUOUS,
The Big Bang Theory Season 12, Episode 22

What? That was AMBIGUOUS.
The Big Bang Theory Season 6, Episode 20

I'm sorry, that's AMBIGUOUS.
ls it five minutes apart
The Big Bang Theory Season 10, Episode 11