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 lecture was
on COSMIC gas clouds.
The Big Bang Theory Season 7, Episode 17

...he never would have found
that stupid little clump of COSMIC schmutz.
The Big Bang Theory Season 2, Episode 4

...of COSMIC radiation at sea level,
but I don't need help.
The Big Bang Theory Season 1, Episode 12

COSMIC background radiation
from the singularity.
The Big Bang Theory Season 12, Episode 13