短语have a big mouth用来形容一个说话声大、爱说闲话而且无法保守秘密的人。
- Jimmy has a big mouth. Yesterday I told him that I am leaving the company and today everybody knows about it.
- I could never be a spy. I have a big mouth!
值得注意的是，短语all mouth常会用在“be all mouth and no trousers”这个表达中，意思是只说不做。
- I bet you haven't asked your boss about that pay rise you talk so much about; you are all mouth and no trousers!