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.

But I can kind of...
see up your SKIRT.
The Big Bang Theory Season 7, Episode 18

That is, underneath your mini SKIRT, huh?
Money Heist Season 1, Episode 8

But I never wear a mini SKIRT, Ángel.
Money Heist Season 1, Episode 8

Unless you have Gravity
on Blu-ray under that SKIRT,
The Big Bang Theory Season 7, Episode 21

Slutty cop only came
with a SKIRT and two badges.
The Big Bang Theory Season 6, Episode 5