別客氣 的英文怎么说?

[1] Don't stand on ceremony.[2] Don't feel like you are imposing.
  Don't feel like you are putting somebody out.[3] Don't be shy.[4] Make yourself at home.[5] Don't back down.[6] Don't hold back.

別那麼正式，放輕鬆點 = Don't stand on ceremony.

別認為你麻煩到別人 = Don't feel like you are putting somebody out. = Don't feel like you are imposing.

別不好意思(例如鼓勵別人表明自己的意見) = Don't back down. = Don't hold back.

鼓勵他人做某些事情(可能有些負面，例如罵人)別客氣 = Don't hold back.