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.

He UNITED 100 warring tribes.
Game of Thrones Season 4, Episode 9

of the United Nations has opened
an investigation into the Cortés case.
Money Heist Season 3, Episode 6

The Starks and Targaryens
have UNITED against us,
Game of Thrones Season 7, Episode 7

and years later, you were granted
an entry visa to the United States.
Breaking Bad Season 4, Episode 8

He's UNITED the Thenns, the Hornfoots,
the ice-river clans.
Game of Thrones Season 4, Episode 1