I'm fit as a fiddle.

I think you are mistaken.

Can/shall we get started?

I'm not satisfied with your work.

It's on me. Tôi trả/Tôi mời bạn/Lượt tôi lần này.... khi mời bạn bè đi ăn và mình giành trả tiền. (Don't: I'll pay the bill)

Could you give me a minute? ~ Leave me alone!

I feel you (~ I understand you)

Beast me (~ I don't know)

I'm broke (~ I don't have money)

Make up my mind (~ I have to decide)

Hit me up later (~ Send me a message)