(idiomatic) An emphatic form of believe me: you (the subject) had better believe me (the speaker).

(euphemistic, slang) Fuck you.

An expression of encouragement, chiefly for a girl or woman.

(idiomatic) Do not concern yourself with it; it is none of your business.

(idiomatic) Used to wish someone luck with a difficult endeavor.

A polite expression used when the speaker is first introduced to someone.

Used to propose marriage to someone

Used to speculate about a slight possibility.

(idiomatic, informal) Used to positively assert the frank honesty of an associated statement of set of statements; equivalent to "to you tell the truth".

In confidence; used to impose an obligation to keep something being discussed secret.