常見例句雙語例句Sth . be used to do sth.是固定詞組，意思是用來做某事。Perfomatives: are the sentences that did not state a fact or describe a state, and are not verifiable. But they are used by the speaker to do sth.既不是陳述事實(shí)也不是描寫狀態(tài)，無法証實(shí)，但被說話者用來做事的。blog.sina.com.cn 返回 used to do sth