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.

Grass is always greener?
The Big Bang Theory Season 8, Episode 18

Khaleesi of the Great Grass Sea,
Game of Thrones Season 6, Episode 1

Put artificial GRASS in my backyard,
The Big Bang Theory Season 10, Episode 22

It murders all other GRASS.
Game of Thrones Season 1, Episode 2

Khaleesi of the Great Grass Sea,
Game of Thrones Season 3, Episode 7