初中英语情态动词公开课课件.ppt

中考复习 词汇专题（情态动词）,考点揭密,重难点解析,典型例题分析,课时训练,考点揭密,掌握情态动词的定义：表示可能、怀疑、允诺、愿望、义务、必要、猜测等的动词是情态动词。,1,2,掌握情态动词的语法特征1） 情态动词不能表示正在发生或已经发生的事情，只表示期待或估计某事的发生。2） 情态动词 除ought 和have 外，后面只能接不带to 的不定式。3） 情态动词没有人称，数的变化，即情态动词第三人称单数不加-s。 4） 情态动词没有非谓语形式，即没有不定式，分词，等形式。,can 可表示能力、允许、可能性、怀疑猜测，意为“能，会，可以”；can't意为“不会，不能，不可以”，还有“不可能”之意。could为can的过去式，用法与can类似，常用于过去时中；could还可用于现在时中表示委婉客气，相当于can；could也可表示惊讶怀疑，不相信，如：He couldn't be a thief.,3,1,can,掌握常用情态动can, could, may, might, must, need, shall, will, should, would等的用法。,考点揭密,考点揭密,2,may表示允许、也许，意为“可以，也许，可能”。对may的一般问句的回答，肯定回答一般是：Yes, please./Certainly./ Sure等，否定回答一般是：Please don't./No，you can't/mustn't. might是may的过去式，与may用法类似，常用于过去时中；用在疑问句中，还可表示委婉客气。,may,考点揭密,3,must 表示必须要做的事，意为“必须，应该”。must一般问句的否定回答用needn't或don't have to,而不用mustn't， mustn't意为“不可以，不能”，表禁止，不许可。另外，must还可表示有把握的推测，意为“一定、肯定”。must的过去式还是must。,must,4,need 作情态动词主要用于问句和否定句中，意为“必要”。need一般问句的肯定回答用 must，否定回答用needn't，如：Need I do it right now?肯定回答：Yes, you must。否定回答：No, you needn't. need作行为动词，有人称、数和时态的变化，后接动词要加to do不定式。,need,在回答以must开头的一般疑问句时，否定式需用need not (neednt)，表示“不必”的意思。如： Must we hand in our exercises today? Yes, you must. ( No, you neednt),考点揭密,5,shall, will用来征求对方意见，shall用于第一人称，will用于第二人称，用来表示意愿；shall用于第二、第三人称，will用于第一人称。,6,would, should为will，shall 的过去式，would用于现在时，表示委婉提出请求、建议或看法，如Would you please not do it again? should还有“应该”的意思，但语气比must 弱。,重难点解析,1,怎样选用can和may,情态动词can和may都能表示“可能性”。如：He may be right. 他可能对。He cant be right. 他不可能对。那么，在表示可能性这个概念时，二者的区别是什么呢？,二者所适用的句子类型不同。一般说来，can多用于疑问句和否定句，表示怀疑或不相信等态度；而may则多用于陈述句（肯定），表示一种揣测。如：,Can it be true? No, it can not be true.Where can they be now?I hear there may be a few copies left.What he said may not be right.,重难点解析,二者所强调的意思不同。一般来说，can强调客观上的可能性，而may则强调主观上的推测或判断。如：,Man cannot live without air or water.She may be in the library, I suppose.She may not be there today.,重难点解析,二者表示的语气不同。在否定句中，can表达的否定语气较强，意为“不可能”；而may表达的否定语气较弱，意为“可能不”或“也许不”。如：,That cannot be true. (=It is impossible that that is true.)That may not be true. (=It is possible that that is not true.),根据以上分析，我们可以归纳为三条原则：(1) 在肯定句中用may不用can;(2) 在疑问句中用can不用may;(3) 在否定句中，若语气肯定，表示“不可能”时用can not，若语气不肯定，表示“可能不”时用may not.,重难点解析,现在时：can与be able to一样，但后者不常用。如：,He can write well.He is able to write well.但be able to后不能接被动语态不的定式。如The star cannot be see. （正）The star is not able to be seen. （误）,重难点解析,2,浅析can和be able to的区别,将来时：can没有将来式，此时要用will be able to。如：,I will be able to speak English in three years.但决定将来是否有能力时，也常用can。如Can you come to see us nest Sunday?,重难点解析,过去时，could表示一般能力，was/were able to表示具体场合的能力。如,My father could speak English.He was able to translate this story into French.How many eggs were you able to get?,Could的否定式也可表示具体场合的能力。The question was so difficult that he wasnt able to/couldnt answer it.,重难点解析,3,比较can 和be able to,can/could 表示能力；可能 (过去时用could), 只用于现在式和过去式(could)。be able to可以用于各种时态。They will be able to tell you the news soon. 他很快就能告诉你消息了,只用be able to a. 位于助动词后。 b. 情态动词后。 c. 表示过去某时刻动作时。 d. 用于句首表示条件。,重难点解析,e. 表示成功地做了某事时，只能用was/were able to， 不能用could。He was able to flee Europe before the war broke out.= He managed to flee Europe before the war broke out.,注意：could不表示时态1）提出委婉的请求，（注意在回答中不可用could）。- Could I have the television on?- Yes, you can. / No, you cant.2）在否定，疑问句中表示推测或怀疑。He couldnt be a bad man. 他不大可能是坏人。,重难点解析,4,比较may和might,表示允许或请求；表示没有把握的推测；may 放在句首，表示祝愿。May God bless you! He might be at home.注意： might 表示推测时，不表示时态。只是可能性比may 小。,成语： may/might as well，后面接不带to 的不定式，意为“不妨”。 If that is the case, we may as well try.典型例题Peter _come with us tonight, but he isnt very sure yet. A. mustB. may C. can D. will答案B. 表可能性只能用may.此句意可从后半句推出。,重难点解析,5,比较have to和must,两词都是必须的意思，have to 表示客观的需要， must 表示说话人主观上的看法，既主观上的必要。,have to有人称、数、时态的变化，而must只有一种形式。但must 可用于间接引语中表示过去的必要或义务。He had to look after his sister yesterday.,My brother was very ill, so I had to call the doctor in the middle of the night.我弟弟病得很厉害，我只得半夜里把医生请来。(客观上需要做这件事)He said that they must work hard. 他说他们必须努力工作。（主观上要做这件事）,重难点解析,5,比较have to和must,在否定结构中： dont have to 表示“不必”mustnt表示“禁止”，,You dont have to tell him about it. 你不一定要把此事告诉他。You mustnt tell him about it.你一定不要把这件事告诉他。,重难点解析,6,must表示推测,must用在肯定句中表示较有把握的推测，意为“一定”。,must表对现在的状态或现在正发生的事情的推测时， must 后面通常接系动词be 的原形或行为动词的进行式。,You have worked hard all day. You must be tired. 你辛苦干一整天，一定累了。（对现在情况的推测判断）He must be working in his office. 他一定在办公室工作呢。比较： He must be staying there. 他现在肯定呆在那里。 He must stay there. 他必须呆在那。,重难点解析,6,must表示推测,must 表示对已发生的事情的推测时，must 要接完成式。,I didnt hear the phone. I must have been asleep.我刚才没有听到电话，我想必是睡着了。,【例1】Where's Mr Li?I have something unusual to tell him. You _ find him.He_Japan.2003 黑龙江 A.may not,has gone to B.may not, has been to C.can't，has gone to D.can't, has been to,C,【例2】 Could I look at your pictures? Yes,of course you _.2003 武汉 A.could B.can C.will D.might,B,典型例题解析,【例3】Where is Jack，please? He_be in the classroom.2003 杭州 A.can B.need C.would D.must,D,【例4】 The boy said he had to speak English in class， but he speak it after class.2003，广州 A.could B. didn't have to C.might D. shouldn't,B,典型例题解析,【例5】These books_out of the reading room.You have to read,them here.2003，辽宁 A.can't take B. must be taken C.can take D. mustn't be taken,D,典型例题解析,1._I open the window?It's hot here. A.Must B.Shall C.Will D.Would2.Go and ask Mr Liu.He _tell you. A.may B.can C.would D.could3._you please tell me the time please? A.Shall B.Will C.May D.Might4._I try out all the ideas? No,you _. A. Must, mustn't B.Need,need C.Must,don't have to D.Must,don't5._I speak to Mr Green，please? A.Will B.Could C.Must D.Would ,B,A,B,C,B,课时训练,6.He said Kate _come to the party.But I don't think so. A.could B.might C.need D.must7.Need I do my lessons right now? Yes,you_. A.need B.can C.should D.must8.Would you like to go swimming with me this afternoon?I'd love to.But I'm afraid I_.I have too much work to do. A.can't B. mustn't C. needn't D.may not9.To make our city more beautiful，rubbish_into the river. A. needn't be thrown B. mustn't be thrown C.can't throw D. may not throw,B,D,A,B,课时训练,10.Don't worry! We can get to the bus station in time and _the early bus. A. don't miss B. can miss C. will miss D. won't miss11.Please don't make any noise in the reading room. _ A. Sorry, I won't. B. Sorry, I can't. C. Yes, I won't. D.OK,I didn't.12.Must I return your digital camera tomorrow. Tina? No, you_. A. mustn't B. may not C. needn't D. won't,A,C,D,课时训练,13.Would you like some more? _I'm full. A.Yes,please. B.I'd love to. C.No,I wouldn't. D.No,thanks.14.You_swim in this part of the lake. It's dangerous. A. mustn't B.may not C. needn't D.won't15.Your e-mail address again? I_quite catch it. Hr Zhou 263.com. A.don't B.can't C.won't D. didn't,A,D,D,课时训练,Thank you!,