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.

Honestly, you over-think everything.
The Big Bang Theory Season 4, Episode 6

Honestly? Sex.
The Big Bang Theory Season 5, Episode 5

Honestly, I thought when
I got married I would,
The Big Bang Theory Season 7, Episode 14

Honestly, I'm tempted
to leave the university.
The Big Bang Theory Season 7, Episode 24

Honestly, I just wanted to meet Mr. Lucas
and say thank you.
The Big Bang Theory Season 8, Episode 19