你不必这么客气。
You do not have to be so polite.
need not; does not have to; not necessarily
Every character draws itself, stroke by stroke. Then grab the brush: trace it yourself and hear the word when you finish.
Nice writing!
Chinese words snap together like bricks. Every word below shares a character with this one, so you are already halfway to knowing it.
你不必这么客气。
You do not have to be so polite.
这件事不必担心。
There is no need to worry about this matter.