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 seem to be implying a back CHANNEL
between me and Penny...
The Big Bang Theory Season 2, Episode 1

...you'd be the toughest kid
on the Disney Channel.
The Big Bang Theory Season 8, Episode 8

and the East coast feed of the
Disney Channel on 290.
The Big Bang Theory Season 5, Episode 24

They're on The Discovery Channel.
The Big Bang Theory Season 2, Episode 19

And every day at 4:00,
you'd come to my house on Channel 68...
The Big Bang Theory Season 6, Episode 22