高一语法必修三unit1情态动词.ppt

人教课标版人教课标版高一高一 必修必修 3情态动词的语法特征情态动词的语法特征1) 情态动词情态动词 不能单独做谓语不能单独做谓语, 除除ought 和和have 外外, 后面只能接不带后面只能接不带to 的不定式。的不定式。 2) 情态动词没有人称情态动词没有人称, 数的变化数的变化, 但有些情但有些情态动词态动词, 如如can、will也有一般式和过去式也有一般式和过去式的变化。的变化。3) 情态动词的情态动词的“时态时态”形式并不是时间区别形式并不是时间区别的主要标志的主要标志, 不少情况下不少情况下, 情态动词的现在式情态动词的现在式形式和过去式形式都可用来表示现在时间、形式和过去式形式都可用来表示现在时间、过去时间和将来时间。过去时间和将来时间。 1) can的主要用法是：的主要用法是： A. 表示体力或脑力的能力：表示体力或脑力的能力： eg. The girl can dance very well. B. 表示说话的推测表示说话的推测事物的可能性等事物的可能性等: eg. Can the news be true? C. 在口语中在口语中, can可以表示请求或允许可以表示请求或允许: eg. Can I sit here? can 和和could：2) could的主要用法是：的主要用法是： A. could 是是can的过去式的过去式, 表示与过去表示与过去 有关的能力和推测有关的能力和推测: eg. We all knew that the young man couldnt be a doctor. B. could可以代替可以代替can表示请求表示请求, 但语但语气较气较can客气、委婉客气、委婉: eg. Could you lend me your dictionary? Could I use your bike? 3) can和和could接动词的完成形式，表接动词的完成形式，表示可能已经做某事。示可能已经做某事。can用在否定和疑用在否定和疑问句中问句中, 表示不相信、怀疑等态度。表示不相信、怀疑等态度。 eg. They cant have gone out because the light is still on.may 和和might ： may 常用来表示：常用来表示： A. 表示请求、允许表示请求、允许;比比can较为正式较为正式: eg. May I come in ? You may go now. B. 表示说话人的猜测表示说话人的猜测: “也许也许” “可可能能”: 通常只用于肯定句和否定句中。通常只用于肯定句和否定句中。 eg. -I believe the man is from England. -But I may be wrong. The guest may arrive this afternoon. 在肯定句中，在肯定句中，may 的可能性比的可能性比can 高，高，may 表示现实的可能性，表示现实的可能性，can 表示表示理论上的可能性。如：理论上的可能性。如： The road may be blocked. 这条路可能不通了。这条路可能不通了。 The road can be blocked. 这条路可能会是不通的。这条路可能会是不通的。 在疑问句中，表示可能性用在疑问句中，表示可能性用can。 如：如：Where can he be? 他会在哪呢？他会在哪呢？ C. 表示祝愿表示祝愿;但语气较正式但语气较正式: eg. May you succeed! May you have a good journey! might 的用法有的用法有: 多在间接引语中表示过去的可能和多在间接引语中表示过去的可能和允许。如允许。如: She said that he might take her bike. 她说他可以拿她的自行车去用。她说他可以拿她的自行车去用。 除了在间接引语中以外，除了在间接引语中以外，might 一般一般不表示过去的可能或者许可。如要表示不表示过去的可能或者许可。如要表示过去的可能可以用过去的可能可以用could, 表示过去的许表示过去的许可可以用可可以用was( were) allowed to 或者或者 had permission to 。 表示现在的可能，其可能性要比表示现在的可能，其可能性要比 may 小。如：小。如： She might go home tomorrow. 说不定他明天会回家。说不定他明天会回家。 表示现在的许可表示现在的许可, 语气比语气比may 较委婉较委婉, 一般用于疑问句一般用于疑问句(包括间接疑问句包括间接疑问句), 不可不可用于肯定句或者否定句。用于肯定句或者否定句。 如如: Might I have a word with you? 我可以和你说句话吗？我可以和你说句话吗？will和和would： 1. will是助动词或是情态动词？是助动词或是情态动词？ will用于构成将来时是助动词。用于用于构成将来时是助动词。用于表示表示“意志意志”“”“决心决心”“”“请求请求”是情态是情态动词。动词。would亦同理。亦同理。 eg. I will tell you something important. 我要告诉你一些重要的事。我要告诉你一些重要的事。 （助动词）（助动词） Will you tell her that Im here? 请您告诉她说我在这儿，好吗？请您告诉她说我在这儿，好吗？ （情态动词）（情态动词） 2. 在疑问句中用于第二人称，提出请在疑问句中用于第二人称，提出请求或询问。求或询问。 eg: If you want help - let me know, will you? 如果你需要帮助如果你需要帮助, 让我知道让我知道, 好吗好吗? Will you type this, please? 请打印这个请打印这个, 好吗？好吗？ Wont you sit down? 请坐下请坐下, 好吗？好吗？ 3. would比比will客气委婉。客气委婉。 eg: Would you help us, please? 请您帮助我们，好吗？请您帮助我们，好吗？ （表请求）（表请求）Id go there with you. 我要和你一块到那儿去。我要和你一块到那儿去。 Teacher wouldnt allow it. 老师不会允许这件事。老师不会允许这件事。（表意愿）（表意愿）（表许可）（表许可）shall和和should： 1. shall用于构成将来时是助动词。用于构成将来时是助动词。 shall用于征求对方的意见，表示用于征求对方的意见，表示 “决心决心” 是情态动词。是情态动词。 eg: Perhaps I shall pay a visit to England this winter. 可能今年冬天我会去英国观光。可能今年冬天我会去英国观光。 （构成一般将来时（构成一般将来时, 助动词）助动词） Shall we go by train, Mom? 妈妈，我们乘火车去好吗？妈妈，我们乘火车去好吗？ （用于征求对方的意见，情态动词）（用于征求对方的意见，情态动词） I shall go at once. 我必须立即去。我必须立即去。 （表（表 “决心决心”，情态动词），情态动词） 2. should表示义务、建议、劝告，意表示义务、建议、劝告，意为为 “应该应该”。 “should+ have+过去分过去分词词” 表示本应该在过去做但没有做。表示本应该在过去做但没有做。 eg: You should keep your promise. 你应该遵守诺言。你应该遵守诺言。 She should have passed the exam. 她应该通过考试的。她应该通过考试的。must和和 have to1.must用于一般问句中用于一般问句中,肯定回答用肯定回答用must否定式用否定式用 neednt或或dont have to，做做 “不必不必”,mustnt表示表示“禁止，不允许禁止，不允许” MustIfinishallassignmentsatatime?Yes,youmust.No,youneednt.I dont like this TV set. We must buy a new one. There was no more bus. They had to walk home.2.表示表示“必须必须”这个意思时，这个意思时，must 和和have to 稍有区别。稍有区别。must着重说明主观着重说明主观看法，看法，have to 强调客观需要。另外，强调客观需要。另外，have to 能用于更多时态。能用于更多时态。 Youmustbethenewteacher.Hemustbejoking.Thereisnobodyhere.Theymusthaveallgonehome.3.must表示对某人某事的猜测表示对某人某事的猜测, 作作“准准是是”, “一定一定” , 一般用于肯定句中。对一般用于肯定句中。对过去发生的事情作肯定判断用过去发生的事情作肯定判断用must have done Hemustcomeandworryherwithquestion,justwhenshewasbusycookingthedinner.Ofcourse，afterIgavehermyadvice，shemustgoanddotheopposite.4. must表示表示“偏要偏要, 硬要硬要”, 指做令人不指做令人不快的事情快的事情 2. A: _ Xiao Feng find the origin of Easter from that book? B: No, he _. 1. A: _ you like to go to a special event with us on Saturday? B: Yes, I _ _.Wouldd like to go with you on SaturdayCouldcouldnt find itExercise 3. A: _ I go with my friend to the harvest festival? B: Yes, you _ _. 4. A: If I want to be a doctor _ I study science? B: Yes, you _. should study scienceMay may go ( with your shouldfriends )5. A: He is very handsome. _ he play the role of the prince? B: No, he _ _. cant play the role of theCanprince 6. A: The neighbour s children are older this year. _ they stop playing tricks at Halloween? B: Perhaps, they _ _. _ _.Mightor Shouldmight stopor should stop playing tricksplaying tricks at Halloweenat Halloween1. -_ I go out to play, mum? -No, you_. You should do your homework first. A. Might; wouldnt B. May; had better not C. Must; mustnt D. Need; mustntB练习坊练习坊I. Choose the correct answer.2. -Where is Emma? -I cant say for sure where she is, but she_ be out shopping. A. can B. should C. must D. mayD3. The room is in a terrible mess; it _ cleaned. A. cant have been B. couldnt be C. may have been D. would beA4. How _ you say that you really understand the whole story if you have covered only part of the article? A. can B. must C. need D. mayA5. There _ be any difficulty about passing the road test since you have practised a lot in the driving school. A. mustnt B. shant C. shouldnt D. needntC6.-There were already five people in the car but they managed to take me as well. -It _a comfortable journey. ( ) A. cant be B. mustnt have been C. shouldnt be D. couldnt have beenD7.The fire spread through the hotel very quickly but everyone _ get out. ( ) A. had to B. would C. could D. was able toD8. Peter _ come with us tonight, but he isnt very sure. A.must B. can C. may D. willC9. - Could I call you by your first name? - Yes, you_. A. will B. could C. may D. mightC10. Sorry, I m late. I _ have turned off the alarm clock and gone back to sleep again. A.might B. should C. can D. willA11.-Excuse me, but I want to use your computer to type a report.-You _ have my computer if you dont take care of it.A.shant B. might not C. neednt D. shouldntA12. -When can I come for the photos? I need them tomorrow afternoon. -They _be ready by 12 : 00. A. can B. should C. might D. needB13. With so much work on hand, you _ to see the game last night. A. mustnt go B. could have goneC. shouldnt go D. shouldnt have goneD14.Johnny, you _ play with the knife, you _ hurt yourself. A. wont ; cant B. mustnt ; mayC. shouldnt ; must D. cant ; wouldntB15.There is no light in the dormitory. They must have gone to the lecture, _? A. didnt they B. dont they C. mustnt they D. havent theyD16. I missed the bus, so I _ go home on foot. A. must B. may C. can D. had toD1. “_ you walk without my help?” Father asked his little son.2. He _ be married, but Im not sure.3. What you said _ be true, but I just couldnt believe you. Canmay / mightmightII. 用括号中所给的情态动词用括号中所给的情态动词(can / could, may / might, will / would, shall / should, must) 填空。填空。4. Marys score on the test is the highest in her class. She _ have studied very hard.5. _ you like to give me a hand when I go upstairs?6. _ we go to the cinema?mustWouldShall7. We _ help him to solve the problem if he asks us to.8. He hurt his foot and _ not play football.9. As students, we _ study hard.willcouldshould 2Find the sentences containing modal verbs in the reading passage.Then usually by lunchtime they would all be sold.What could have happened?Nothing could be better”Something terrible must have happened if He could not believe his eyes.Perhaps he should go to the library and find out.He had better do some research!Even though her customers might get thin after eating Yong Huis foodThey would become tired very quickly.Modal verbsa. should, ought to都可表示都可表示“应该应该”。ought to用于用于表示按道理应当表示按道理应当，常指，常指客客观的义务或责任观的义务或责任，大多数情况下可用大多数情况下可用should代替，但比代替，但比should语气重语气重。I should help her because she is in trouble.You ought to take care of the baby.b. 表示劝告、建议或命令时，表示劝告、建议或命令时，should和和ought to可通用可通用，但在，但在疑问句中常用疑问句中常用should。ought to的否定式为的否定式为oughtnt to或或ought not to。You should / ought to go to class right away.Should I open the window?What should we do next?c. should, ought to都可表示推测。都可表示推测。He ought to / should be home by now. This is where the oil ought to / should be. should 和和ought to 后面跟动词不定式的完成后面跟动词不定式的完成式式, 其肯定句表示其肯定句表示“过去应该做而未做过去应该做而未做”, 其其否定句则表示否定句则表示 “过去不该做但做了过去不该做但做了”。You should/ought to have made the decision a week ago.I shouldnt have made such a foolish mistake. 多数情况下，多数情况下，ought to可与可与should互换使用。互换使用。ought to的反意疑问句用的反意疑问句用shouldnt替代。替代。注意注意You ought to have helped him with his English, _?A. wont you B. ought not youC. shouldnt youD. wouldnt you 2. must和和have to must的用法的用法 1) 表示主观的义务和必要表示主观的义务和必要, 主要用于肯主要用于肯定句和疑问句定句和疑问句, 意思为意思为 “必须必须，得得，要，要”；由；由must引起的疑问句，引起的疑问句，肯定回答要用肯定回答要用must或或have to, 否定回答要否定回答要用用neednt或或dont have to, 意思是意思是“不不必必” ； must的否定形式的否定形式mustnt表示禁止，意表示禁止，意思是思是“不能，不许不能，不许”。如：。如： Must I finish the task right now? 我现在必须完成这个工作吗？我现在必须完成这个工作吗？ Yes, you must. / Yes, you have to. 是的。是的。 (No, you neednt. / No, you dont have to. 不，不必。不，不必。) You mustnt come here without permission. 未经允许，你不能来这儿。未经允许，你不能来这儿。 have to 的用法的用法 1) must表示一种主观的需要，而表示一种主观的需要，而have to表示一种客观的需要，意思表示一种客观的需要，意思是是“不得不不得不”。 如：如： I have to attend an important meeting this afternoon. 今天下午我不得不参加一个重要的今天下午我不得不参加一个重要的会议。会议。 Mother is out, so I have to look after the shop. 妈妈不在家，因此我不得不照看妈妈不在家，因此我不得不照看商店。商店。 2) have to 的否定形式是的否定形式是dont have to, 相当于相当于neednt。如：。如： They dont have to buy a computer at present. 他们目前没有必要买电脑。他们目前没有必要买电脑。 【考例【考例】The boss has given everyone a special holiday, so we _ go to work tomorrow. (上海上海 2007春春)A. cant B. mustntC. neednt D. shouldnt【点拨【点拨】考查情态动词。根据题意考查情态动词。根据题意, 可知可知这里表示这里表示“没有必要没有必要”, 故只能选故只能选C项。项。【考例【考例】What do you think we can do for our aged parents?You _ do anything except to be with them and be yourself. (重庆重庆 2007)A. dont have to B. oughtnt toC. mustnt D. cant 【点拨【点拨】根据题意根据题意“除了和他们呆在一除了和他们呆在一起做你自己外起做你自己外, 没有必要做任何事情。没有必要做任何事情。”可知这里选择可知这里选择dont have to表示表示“不必不必”。故选故选A项。项。3. must和和needa. need作情态动词时作情态动词时, 只能用于疑问句只能用于疑问句和否定句。构成否定句和疑问句时不和否定句。构成否定句和疑问句时不借助于助动词借助于助动词do。 Need I finish the work today? Yes, you must. / No, you neednt.b. must的肯定形式表示的肯定形式表示“必须必须”，否定，否定式式 表示表示“禁止、严禁禁止、严禁”。 You must come here. You mustnt take the book away from the library. 用下列图片造句。用下列图片造句。做适当的运动做适当的运动 You should do some sports. 慢慢地进食，并有助消化。慢慢地进食，并有助消化。 You ought to eat slowly and its good for digestion. You should help to set the dinner table. You should keep your room clean.We must listen to the teacher carefully.We mustnt eat in class.You ought to hand on the homework on time.You shouldnt be late for school.We should ask question actively.We shouldnt make noise in class.Make sentences 1. 你每天最少要练习一小时口语。你每天最少要练习一小时口语。 You must practise speaking English at least an hour a day 2. 我每天不得不练习一小时口语！我每天不得不练习一小时口语！ I have to practise speaking English an hour a day！ 3. 你应该每天练习不止一小时。你应该每天练习不止一小时。 You ought toshould practice English for more than an hour 4. 你应该读一下这个。它写得很好。你应该读一下这个。它写得很好。 You ought toshould read this Its very good 5. 你必须读这个。写得精彩极了！你必须读这个。写得精彩极了！ You must read thisIts marvelous！ Please choose a proper phrase and according to the situations complete the sentences by using should(not)orought(not)to. 1. Lisa needs a change. She _. 2. My salary is very low. You _. should/ought to take a few days offshould look for a new job 3. Nick always has difficulty getting up. He _ _. 4. What a beautiful view! You _. 5. Billys room isnt very interesting. He _ _.ought not to /shouldnt go to bed so lateshould take a photoshouldnt/ ought not to use hercar so muchChoose suitable modal verbs below to complete the following dialogues.ought/oughtnt to should/ shouldnt mustnt neednt (dont) have to will can/ cant1 Sam: How can I grow thinner, Mum?Mum: Well, you _ eat food with plenty of fibre that helps you digest better. And you _ stop drinking cola or eating sweet food.have to should Sam: Does it mean I _ eat my favourite fried chicken any more?Mum: Not exactly, if you love fried chicken, you _ give it up. Just eat it less often. You _ worry too much: a little fried chicken _ do you good! shouldnt needntdont have to/ neednt/ shouldnt will2 Doctor: You are sick because youve eaten poisonous mushrooms. Where did you get them?Lucy: I picked them in the forest. I know we _ eat fresh vegetables.Doctor: Oh, but you _ eat them until youre sure they are not poisonous.Lucy: Thank you, doctor. Ill be more careful next time.have tomustnt 3 Charles: I wish I could see things clearly in the dark. Tom: Eating carrots _ help you see better. You _ eat some every day.ought to should1. _ to discuss something with someone so that you can make a decision together 2. _ to change food that you have just eaten into substances that your body can use 练习坊练习坊I. 根据下列英文解释写出所缺的单词。根据下列英文解释写出所缺的单词。consultdigest3. _ a long pointed orange vegetable that grows under the ground 4. _ containing poison or producing poison carrotpoisonous1. For a long time, Ive built my business with people who are _ (精力旺盛的精力旺盛的), creative, and happy about their work.2. This rich food doesnt _ (消化消化) easily.energeticdigest根据下列各句句意及所给单词的汉语根据下列各句句意及所给单词的汉语提示提示, 写出各单词的正确形式。写出各单词的正确形式。3. The dish of boiled beef and _ (胡萝卜胡萝卜) tastes good.4. An increasing number of people are _ (请教请教) their accountants about the tax laws. 5. This medicine is _ (有毒有毒) if taken in large quantities.carrotconsultingpoisonousmust; oughtnt to; dont have to; couldnt;mustnt; neednt; cant; have toII. 用所给的情态动词填空。用所给的情态动词填空。1. You _ go on working because you look so tired now. 2. The weather turned out to be fine yesterday. I _ have had the trouble to carry my umbrella with me. oughtnt to / dont have to needntmust; oughtnt to; dont have to; couldnt;mustnt; neednt; cant; have to3. If you earn more than 5,000, you _ pay tax. 4. You _ play now!You shall finish your homework first! 5. I know things are hard with you, but you _ try to get over the difficulties.have tomustntmust / have tomust; oughtnt to; dont have to; couldnt;mustnt; neednt; cant; have to6. I didnt see her at the meeting this morning; she _ have spoken at the meeting. couldnt / cant1. I thought you _ like something to read, so I have brought you some books. A. may B. might C. would D. must 2. Where is my pen? I _ it. A. might lose B. would have lost C. should have lost D. must have lost高考链接高考链接3. I didnt hear the phone. I _ asleep. A. must be B. must have been C. should be D. should have been4. -Is John coming by train? -He should, but he _ not. He likes driving his car. (2002高考题）高考题） A. must B. can C. need D. may5. It has been announced that candidates (候选人候选人) _ remain in their seats until all the papers have been collected. (2002上海上海高考题）高考题） A. can B. will C. may D. shall6. -I heard they went skiing in the mountains last winter. -It _ true because there was little snow there. (2002北京北京高考题高考题) A. may not be B. wont be C. couldnt be D. mustnt be7