Good Riddles

Question: what does not move outside (the surface)but moves inside ?

Question: We are 5 little items, and you can find us all in a tennis court.

Question: I never was. Am always to be. No one ever saw me, nor ever will. And yet I am the confidence of all who live and breathe. What am I ?

Question: What do you call a fly without wings?

Question: We hurt without moving. We poison without touching. We bear the truth and the lies. We are not to be judged by our size. What are we?