1、Section Grammar情态动词,思维导图,情态动词表示说话人对某一动作或状态的态度，但本身词义不完全，不能单独作谓语动词，必须和动词原形连用。情态动词没有人称和数的变化。每一个情态动词都有自己的具体含义和特点。(1)表示能力(此时could为过去式) He can use the computer skillfully now，but he couldnt last year. 他现在能熟练使用电脑了，但去年他不会。,1.can (could),(2)表示推测(用于否定句和疑问句) That cant be Mary.Shes in hospital. 那不可能是玛丽。她住院了。 So
2、meone is knocking at the door.Who can it be? 有人在敲门，可能是谁呢？ (3)表示许可和请求(could用来表示“请求”时，是委婉的说法，回答时只用can) Could I have a look at your new iPhone? 我可以看一看你的新苹果手机吗？ Of course，you can. 当然可以。,(4)用在肯定句中，表示某人/某物一时的特点，可译为“有可能，有时会”。 Even experienced teachers can make mistakes. 即使是有经验的教师也可能出错。 温馨提示 can和be able to的
3、异同 (1)can表示能力，只用现在时和过去时(could)，而be able to有各种时态。 They will be able to tell you the news soon. 他们很快就能告诉你那个消息了。 (2)表示成功地做了某事，只能用was/were able to，而不能用could。 The fire spread through the hotel very quickly，but everyone was able to get out. 大火在整个宾馆内蔓延开来，但每个人都成功逃出来了。,2.may (might),(1)表示请求、许可。might语气更委婉一些。
4、You may take my dictionary as long as you dont keep it too long. 只要使用时间不太长，你可以把我的词典拿走。 温馨提示 如何回答may的问句 may引导的疑问句，肯定回答用“Yes，you may.”；否定回答用“No，you mustnt./No，you cant./No，you had better not.”。 (2)may和might表示可能性不大的推测，但may比might可能性大，常用于肯定句和否定句，不能用于疑问句。常译为“有可能”，may/might not意思是“可能不会”。 Are you coming to
5、Marys party? 你打算去参加玛丽的聚会吗？,Im not sure.I might/may go to the concert instead. 不能确定。我有可能去参加音乐会。 They might be having a meeting，but Im not sure. 他们有可能在开会，不过我不确定。 (3)may/might as well动词原形，意为“不妨”。 If that is the case，you might as well try. 如果事情是这样的，你不妨一试。 (4)用于祈使句中表示祝愿。 May you succeed！祝你成功！,3.must,(1)表
6、示必须。其否定形式为mustnt，意为“不许，禁止”。回答must的问句时，否定常用neednt/dont have to，表示“不必”。 Your homework must be handed in before the class is over. 你的作业必须在下课之前交上。 The children have gone to bed.You mustnt make any noise. 孩子们已经睡了。你们不准吵闹。 Must we hand in our exercise books now? 我们现在必须要交练习本吗？ No，you neednt/dont have to. 不，
7、不必。,(2)表示推测。意为“肯定，一定”，只用于肯定句中。 Janes light is on.She must be at home.She cant be out. 简的房间里开着灯。她一定在家，不可能出去。 (3)表示“偏要；坚持要”。常常表示与说话人愿望相反及不耐烦。 If you must leave，do it quietly. 如果你一定要离开，那就悄悄地走。,温馨提示 must和have to的异同 have to含义与must相似，两者往往可以互换使用，但must与have to有下列几点不同： (1)must表示说话人的主观看法，而have to 则往往强调客观需要。 (
8、2)must一般用于一般现在时，have to则有更多的时态形式。 I have to wait here because I have no umbrella with me. 我不得不在这儿等，因为我没带伞。 Everyone must keep the law. 人人都要守法。,4.Shall (1)用于第一、第三人称的疑问句中表示征求意见或请求指示。 What shall we do this evening? 今晚我们做什么？ Manager，someone is waiting for you.Shall he come in? 经理，有人在等你，他可以进来吗？ (2)用于第二、第
9、三人称的陈述句表示说话人的意愿，有“命令、允诺、警告、威胁和允许”等意思。 You shall have my answer tomorrow. 你明天可以得到我的答复。(允诺) You shall be sorry for what you did today one day. 总有一天你会对你今天所做的事后悔的。(警告),5.should (1)表示义务。意为“应该”。 You should be polite to your teachers. 你对你的老师应该有礼貌。 (2)表示推测。意为“想必一定；照说应该”。 They should be there by now，I think.
10、 我想他们可能在那儿了。 (3)表示惊异。意为“竟然”。 Its surprising that Tom should cheat in the exam. 汤姆竟然在考试中作弊，真是不可思议。,6.will (would) (1)表示意愿。用于各种人称的陈述句中。 I will do anything for you. 我愿为你做任何事。 They would not let him in because he was poorly dressed. 他们不让他进去，因为他衣着破旧。 (2)表示请求。用于疑问句中。would语气更委婉。 Will you please take a mess
11、age for him? 你能给他带个口信吗？ Would you mind cleaning the window? 请你把窗户擦一下，好吗？,(3)表示某种倾向或习惯，would表示过去的习惯。 The boy will sit there hour after hour looking at people going by. 那个男孩常常坐在那里好几个钟头，看着人们走过。 Every time she was in trouble，she would go to him for help. 每次遇到麻烦，她都会向他求助。 温馨提示 would和used to的区别 (1)would表示过
12、去习惯性的动作，不涉及现在的情况。 Each time his mothers birthday came，he would buy her a present. 每次到他母亲生日的时候，他都要给她买一件礼物。 (2)used to表示过去经常性或习惯性的动作或状态，现在已经不做了。 He used to be late for school，but now he is used to getting up early. 他过去常常上学迟到，现在他已习惯早起。,7.need 和dare (1)need 作情态动词，表示“需要；必须”；dare表示“敢；敢于”。常用于否定句和疑问句中，后接动词原
13、形，否定形式分别为need not和dare not。 You neednt answer his question immediately. 你不必立即回答他的问题。 If he dare go，Ill go with him. 如果他敢去，我也跟去。,(2)need和dare常用作实义动词，有时态、人称和数的变化，后面可接带to的不定式。 You dont need to be told twice. 不必告诉你两遍。 Tom didnt dare to do it. 汤姆不敢做那件事。,.用适当的情态动词填空，必要时使用否定形式,1.Since you have finished you
14、r work，there is no point in staying any longer；you _ as well go home. 2.You can keep the book for a month.After that you _ return it on time. 3.The boy _ speak three languages when he was 12 years old. 4.It never occurred to me that she _ lie to me again. 5.No student _ go out of the school campus a
15、fter 10：00 at night without permission according to the school regulations. 6.You _ get the machine repaired this week.I wont need it until next month.,may,must,could,should,shall,neednt,7.It _ be the vocabulary that caused you the problem in the exercise because you know a lot of words. 8.Lucy does
16、nt mind lending you her dictionary.She _.Ive already borrowed one. 9.I really _ thank you enough.Its been an amazing day! 10.She _ not go out alone at night.,couldnt,neednt,cant,dare,.单句改错,1.Could I borrow your book?Yes.Of course you could._ 2.You may be carefulthe traffic lights arent working._ 3.It has been announced that students will remain in their seats until all the papers have been collected._ 4.You havent eaten anything since morning，so you can be hungry._ 5.The boy can speak three languages when he was 12 years old._,第二个couldcan,maymust,willshall,canmust,cancould,
