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.

...I could teach you
some RUDIMENTARY physics.
The Big Bang Theory Season 3, Episode 10

simple RUDIMENTARY instructions.
Too stupid to re...
Breaking Bad Season 2, Episode 4

Someone with a RUDIMENTARY
understanding of science...
The Big Bang Theory Season 6, Episode 3

Sheldon, this is a RUDIMENTARY collection
of neurons.
The Big Bang Theory Season 10, Episode 8