牛津高中英语模块四-情态动词

1、精选优质文档-倾情为你奉上情态动词一 情态动词类型：1） 只作情态动词：must, can(could), may(might), ought to2） 可作情态动词也可作实义动词：need, dare3） 可作情态动词，也可作助动词：shall(should), will(would)2 情态动词分别讲解1.Must1)“必须，一定要” 可用于肯定句，表示说话人的主观意志，否定句表示禁止听话人干某事，疑问句中表示征求听话人意见，是否必要做某事。 We must be confident in ourselves. You mustnt smoke in the classroom. -Mus

2、t we hand in our exercise in class? -Yes, you must. / No, you neednt/ dont have to.2)表推测，“必然，必定”只用于肯定句，不用于疑问否定句中。 (1) 现在的肯定推测：must do He must be mad. (2) 现在正在进行的动作：must be doing They must be waiting for us. (3）过去的肯定推测：must have done The door is locked. They must have left.3)“偏要，硬要”表示不耐烦。 Must you sm

3、oke here?2.Can 1)“能，会”强调人和动物所具有的能力。 Ducks can swim. I can speak English. 2)“可以，许可”You can smoke here. 3)表示事物发生的可能性，表“推测”。肯定句：理论上、客观上的可能性。Jiangsu can be warm in July.疑问句或否定：具体事实的可能性。表示疑惑，惊讶或者不相信的意思。How can he be rude to you?3.Could 1)can的过去式：“可能，许可”He told me that he could lift more than 100 kilogram

4、s. The teacher tome me that I could hand in my homework later. 2)could提要求，比can更委婉。 -Could I ? Yes, you can. Can you? -Yes, I can. 3)对过去情况的推测：could （not）have done : (1)对当时情况推测：（当时可能/ 不可能）You could have hurt someone.(有可能做了，也有可能没做) (2)虚拟（对过去）（本来可以/ 不可以）I could have gone to help you. Why didnt you ask m

5、e?(本来可以却没做)4.May 1)许可，允许： You may join us in the game. 注意否定回答：-May I smoke here? -No, you cant/ mustnt./ -No, youd better not/ Im afraid not. 2)可能。不用于疑问句。Youd better take a map with you, or you may lose your way. 注意：May he is innocent of the robbery?(错，换成can/ could) 3)may have done: 推测，不用于疑问句。也没有虚拟意

6、味。 Our teacher may have mistaken my mother for my sister.(可能性)5.Could 1)作may 的过去式。表过去的“许可，允许”用于间接引语。 He asked “Can/ May I sit down?” He asked if he could sit down. 2)对现在情况推测，可能性比may 小。He might be here on time, but I am not sure. 3)用于疑问，客气委婉的提出请求。 -Might I come in? -Yes, you may. 4)might have done= c

7、ould have done对过去事情的推测，可能做了。还可用于虚拟 He might have got caught in the shower. You might have persuaded him into giving up the idea, but you didnt try your best.(虚拟)6.Should/ Ought to 1)应该，应当（义务） :You should stick to your opinion. 2)推测，用于陈述句。“按理应当，估计”：They should be there by now, for they have been away

8、 for two hours. 3)should (not) have done 本应该/ 本不应该 You shouldnt have scolded the boy for he has tried his best.(本不应该却做了) 4)竟然：从句中用来表示惊讶，不以为然: He should have fallen asleep in the class.7.Shall 1)主语的意愿决心。用于第一人称：I shall follow you wherer you go. 2)表示建议/请求，用于一，三人称疑问句：Shall we go for a walk? 3)表示说话人给予对方的

9、允诺，命令，警告，威胁，决心等。用于二，三人称 You shall fail of you dont work harder.(警告) If you finish the work ahead of time, you shall have a week off.(许诺) Nobody shall stay in the class when class is over.(命令)8.will/would 1)表意愿（would表过去意愿）:I will make him change his mind even if I stay up all night. They asked us if

10、we would have a look-round first. 2)表请求，建议（用于第二人称）（would 语气更委婉） Will you drop in and have a chat with me ? Would you come to my office when it is convenient? 3)表示倾向，习惯（肯定句）总是，会 （否定句）不肯，就不 （would表过去的习惯） A drowning person will catch at a straw. The old couple would take a walk on fine afternoons.9.Need/ Dare 1)情态动词：need /dare ( not) do sth. Need/Dare+主+do？实义动词：need /dare to do sth. dont need/ dare to do sth. Do+主+need/ dare to do sth?Need you go so soon? Do you nee