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 SUBSTANCE burns so hot,
it melts flesh like tallow.
Game of Thrones Season 2, Episode 5

The SUBSTANCE is fire given form.
Game of Thrones Season 2, Episode 5

Manufacture of a Schedule II
controlled SUBSTANCE
Breaking Bad Season 2, Episode 4

Do you think the coffee had
any other SUBSTANCE?
Money Heist Season 3, Episode 7

It's useful for calculating the number
of atoms in a SUBSTANCE,
The Big Bang Theory Season 9, Episode 10