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 didn't do it for POWER.
You didn't do it for glory.
Game of Thrones Season 5, Episode 1

But a man without friends
is a man without POWER.
Game of Thrones Season 2, Episode 4

is the POWER to transmute
chemical elements.
The Big Bang Theory Season 7, Episode 3

What if evil strikes
and my POWER ring runs low?
The Big Bang Theory Season 3, Episode 12

Overconfidence from his robot's
massive size and its overwhelming POWER.
The Big Bang Theory Season 2, Episode 12