for, during, through(A) for后接“一段时间”,表示某事持续多久,多与完成时连用。如:She has been ill for several days. 她已经病了几天了。(B) during表示“在……期间”。如:I went to France for two weeks during the summer. 夏天我去了法国两个星期。(C) through表示“一直…