情态动词must,have to,have got to的用法

1、太原育英中学 夏冰,情态动词 must，haveto，have got to 的用法,你 去睡一觉。 2. 你 邀请他。 3. 你 照你父母的话办。 4. 你 抽这么多的烟。,Youd better get some sleep.,Youd better not invite him.,You should do what your parents tell you.,You oughtnt to smoke so much.,最好,最好不,应该,不应该,必须,不许,不得不,不必要,You must get some sleep.,You mustnt invite him.,You have

2、 to do what your parents tell you.,You havent got to smoke so much.,Model verbs (),must,have to,have got to,must not / mustnt,dont have to,havent got to / hasnt got to,Must sb?,Do / Does sb. have to ?,Have / Has sb. to ?,（必须、应当）,（必须、不得不）,表示义务、命令或必要，后面接不还to的动词学定式。 Soldiers must obey orders. We must k

3、eep our word. 2. must 用在否定句结构中表示“不允许、禁止” He must not leave his room. You mustnt smoke in the office. 3. must用在一般疑问句中，肯定回答用must，否定回答用neednt 或dont have to Must I hand it in before five? No, you _. Yes, you _.,you neednt. / dont have to,you must,must的用法,have to和have got to 的用法,have to 由have + to组成。因此具有

4、have的各种时态。 He is an invalid and has to have a nurse. She knew what she had to do. I shall have to reconsider my position. He is always having to exercise judement. 2. 在口语中，have got to 也可以表示义务和需要， 与have to 基本同义。 He has got to go right now. He hasnt got to go just yet.,must和have to的区别,含义不同： must 表示说话人

5、的主观思想，强调个人意志和主观的决心。 have to侧重于客观上的必要，强调客观条件作用的结果。 You must do it now. I have to go now.,3. 否定含义不同 在否定句中, have to表示不需要，must则表示不允许。 You dont have to go there. You mustnt go there.,2. 适用时态不同 must 只能用于一般现在时和一般过去时，（在间接引语中） have to 可用于更多的场合。 She said she must do well in her English.,Exercises,Dont be late again. You _ be here on time. A. may B. can C. must D. neednt You _ do it even if you dont want to. A. cant B. mustnt C. neednt D. have to 3. Must I take a bus? No, you _. You can walk from here. A. mustnt B. dont C. don t have to D. had better not to 4. It is rather cold here. Shall we light a fi