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.

Just a suggestion.
You might look down
at the floor with REMORSE.
Breaking Bad Season 4, Episode 4

I've realized that the most genuine way
to demonstrate the REMORSE I feel is
The Big Bang Theory Season 9, Episode 13

that REMORSE, but not...
Money Heist Season 1, Episode 7