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.

"And who performed that HEROIC act?"
The Big Bang Theory Season 3, Episode 16

I took the liberty of burning us a mix
of HEROIC questing music.
The Big Bang Theory Season 4, Episode 19

Yes. And look, now you have a photo
to remember that HEROIC day.
The Big Bang Theory Season 3, Episode 16

You recall that HEROIC engagement?
Game of Thrones Season 3, Episode 6

...to one of the most HEROIC acts
I've ever seen in, like, ever."
The Big Bang Theory Season 3, Episode 16