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.

the calculation
of nuclear MATRIX elements.
The Big Bang Theory Season 7, Episode 20

You can see the MATRIX, can't you?
The Big Bang Theory Season 1, Episode 12

Multiplied by a MATRIX
of negative I comma zero...
The Big Bang Theory Season 5, Episode 7

I'm in the MATRIX, Leonard;
I see everything.
The Big Bang Theory Season 5, Episode 10

I haven't seen him this stuck since he
tried to figure out the third Matrix movie.
The Big Bang Theory Season 3, Episode 14