Unit14Unit141. 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。You’d better get some sleep.You’d better not invite him.You should do what your parents tell you.You oughtn’t 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 mustn’t invite him.You have to do what your parents tell you.You haven’t got to smoke so much.Model verbs (Ⅱ)musthave to have got tomust not / mustn’tdon’t have to haven’t got to / hasn’t got to Must sb…?Do / Does sb. have to …?Have / Has sb. got to …?（必须、应当）（必须、不得不）1.1. 表示义务、命令或必要，后接不带表示义务、命令或必要，后接不带 toto 的动词不定式。的动词不定式。 Soldiers must obey orders.Soldiers must obey orders. We must keep our word.We must keep our word.2. must 2. must 用在否定句结构中表示用在否定句结构中表示““不允许、禁止”不允许、禁止” He must not leave his room.He must not leave his room. You mustn’t smoke in the office.You mustn’t smoke in the office.3. must3. must 用在一般疑问句中，肯定回答用用在一般疑问句中，肯定回答用 mustmust ，否定，否定回答用回答用 needn’t needn’t 或或 don’t have todon’t have to —— —— Must I hand it in before five?Must I hand it in before five? —— —— No, you _________________________.No, you _________________________. —— —— Yes, you ______________.Yes, you ______________. needn’t. / don’t have to needn’t. / don’t have to mustmust1.1. have to have to 由由 have + tohave + to 组成。因此具有组成。因此具有 havehave的各种时态。的各种时态。 He is an invalid and has to have a He is an invalid and has to have a nurse. nurse. She knew what she had to do.She knew what she had to do. I shall have to reconsider my position.I shall have to reconsider my position. He is always having...
