第1个回答 2013-09-21
have to 是客观的情况，不以人的意愿为前提，人是无法改变这个状态的。如My mother was ill yesterday, I have to take care of her. or ,It is raining heavily,we have to stay in the classroom. 而 must 则是主观情况,可做可不做的，没有义务一定要做。如My room is dirty, my mother says that I must clean my room.如果我不嫌弃 ，我也可以不用打扫，含有主观意志。