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.

You know if my clothes get
too soft it makes me SLEEPY.
The Big Bang Theory Season 5, Episode 6

You know if you stay up all night,
you're going to be SLEEPY tomorrow.
The Big Bang Theory Season 6, Episode 22

Now, rise and shine,
SLEEPY head.
The Big Bang Theory Season 5, Episode 15

♪ Happy kitty, SLEEPY kitty
The Big Bang Theory Season 12, Episode 19

Sleepy kitty...
The Big Bang Theory Season 2, Episode 21