助动词和情态动词课件(方案C).ppt

情态动词 v情态动词的类型 1、只作情态动词的有：must, can(could), may(might), ought to; 2、可作情态动词也可作实义动词的有： need, dare(美语中常用作实义动词）； 3、可作情态动词也可作助动词的有: shall(should), will(would); 4、具有情态动词的某些特征的有： have(had) to, used to. 情态动词的特征 1、有一定的词义，但不能单独作谓语，它们要和行 为动词或连系动词连用，构成谓语。 2、适用于主语的各种人称和数have to例外，主语 是第三人称单数时，要用has to）。如： We/ He must work hard. 我们/他一定要努力工作。 I have to walk home. 我得步行回家。 He has to walk home. 他得步行回家。 3、后面接原形动词，即不带to的不定式（ought to, have to, used to本身带有to）。如： He may lose his way. 他可能会迷路。 You ought to obey the law. 你应该遵守法律。 4、具有助动词的作用，即可用来构成否定句、 疑问句及用于简明答语。如： - I cant swim. Can you swim? - No, I cant either. -我不会游泳。你会游泳吗？ - 我也不会 。 题组训练 句子改错： 1）You ought to follow the teachers instructions, oughtnt you to ? (去掉最后一个 to) 2）You neednt to go there right away. (去掉to) 3) He dares go there by himself at night. (dares to go) 4) How dare you to say that to your parents? (去掉第一个 to) 5) The building dating from 1916 need to be repaired. (needs to be) 表能力 1、表示现在的或一般的能力： 表示现在的或一般的能力用can或be able to， 一般的能力即你无论什么时候想做就能做到的能 力。 表示现在的或一般的能力时，can比able to 更普遍。如： A computer cant think for itself; it must be told what to do.（一般能力） He is a native speaker of English, so he can of course speak English quite well.（一般能 力） I am starving to death. I can eat two bowls of rice now.（现在的能力） 练习： The biggest problem for most plants, which _ just get up and run away when threatened, is that animals like to eat them.(07 湖南) A. shant B. cant C. neednt D. mustnt 答案： B，句意为：对绝大多数受到威胁时而不能 起身逃跑的植物来说，最大的问题是动物喜欢吃它 们。情态动词can 可以表示人的能力和物的性能， 故选B表示对能力的否定。 2、表示将来的能力：will be able to 如： If you have a good sleep, you will be able to work our this problem. 如果你睡个好觉，那么你就能做出这个题目。 3、表示过去的能力： could表示过去一般的能力， 但不表示做或未做某事； was/ were able to表示过去有能力并且成功地做了某事 ， 相当于managed to do something/ succeeded in doing something； “could have +过去分词”表示过去有能力但未做。 如 ： She could / was able to sing like an angel when she was a child.（过去一般的能力） The fire spread through the hotel very quickly but everyone was able to get out.（ 过去有能力并且成功地做了某事） I could have worked out the problem, but I didnt.（过去有能力但未做） 题组训练 根据句意填入情态动词的正确形式： 尽管很累了，那些冬泳者还是游过了那条河。 Tired as they were, the winter swimmers _ swim across the river. ( were able to ) 老师跟我谈了很久，我终于被他说服了。 The teacher talked with me for a long time, and eventually, he _ make me believe him. (was able to) 表示推测情态动词的重要用法. 肯定的推测 可能的推测 否定的推测 疑问的推测 must/shoul d 对将来 对现在 对过去情态动词 may, might cant, couldnt can, could + V + V + have done/ 常见must be must be doing have been doing + V. + V. + have done + be doing /have been doing 可以用not表示“可能不” +V. + V . + have done + be doing / have been doing + V. + V. + have done + be doing P.S: 1.在反意疑问句中，当附属部分含有表示推测 意义的must时，疑问部分的助动词应与must后面的 动词在非推测情况下的用法保持一致。 He must be a worker, isnt he? （现在）他准时个 工人，是吗？ You must have learned English for many years, havent you? （完成时）你一定学了好多年英语， 是吗？ 比较： It must have rained last night, didnt it? （过去） 昨晚一定下雨了，是不是？ He must have arrived by yesterday morning, hadnt he? 2. can可用于肯定句中表示客观的（理 论的）可能性，而表示具体事情实际发 生的可能性时，can一般不用于肯定句 。 Accidents can happen on such rainy days.（表客观的可能性） Peter may come with us tonight, but he isnt sure yet.(实际可能性不用 can) vcan 常用于否定句、疑问句或感叹句中 ，表疑惑、惊讶或不可能等意思，could 既可用于肯定句又可用于否定句、疑问 句中。 v This cant / couldnt be done by him. 这不可能是他干的 (表不可能、不相信) v Can this be done by him? (表疑惑、惊 讶) v Mr. Bush is on time for everything. How can it be that he was late for the opening ceremony? (表疑惑、惊讶) 1. I dont know where she is, she _ be in Wuhan. 2. At this moment, our teacher _ our exam papers. 这时，我们老师想必在批改试卷。 3. The road is wet. It _ last night. (rain) 4. Your mother _ for you. 你妈妈一定一直在找你。 may must be marking must have rained must have been looking 5. Philip _ seriously in the car accident. 菲利普可能在车祸中受了重伤. 6. -Linda has gone to work, but her bicycle is still here. -She _ (go) by bus. 7. Mike _ his car, for he came to work by bus this morning. 迈克一定还没有找回他的车，因为早上他是坐 公共汽车来上班的。 may (might) have been hurt may (might) have gone cant have found 1 - Hi, Tom. Any idea where Jane is ? - She _ in the classroom. I saw her there just now. （2009 重庆） A. shall be B.should have been C. must be D. might have been 2 - What do you mean, there are only ten tickets? There _ be twelve. （2009全国） A. should B. would C. will D. shall 3 The traffice is heavy these days. I _ arrive a bit late, so could you save me a place? （2009辽宁） A. can B. must C. need D.might 4（2009上海）It _ have been Tom that parked the car here, as he is the only one with a car. A. may B. can C. must D.should 5（2009安徽）Some people who dont like to talk much are not necessarily shy; they _ just be quiet people. A. must B. may C. should D. would 6、(2008湖南)You dont have to know the name of the author to find a book. You _find the book by the title. A. must B. need C. can D. would 7、(2008 福建) It is usually warm in my hometown in March, but it _ be rather cold sometimes. A. must B. can C. should D.would 8（2009北京）One of the few things you _ say about English people with certainty is that they talk a lot about the weather. A. need B. must C. should D. can 根据句意，选用can,may, 和must填空。 1. Anybody _ make mistakes. 2. Mr. Read looks pale. He _ be ill. 3. Mr. Read is in poor health. He _ be ill at any time. 4.- Look, someone is coming. Who_ it be? - It _ be the headmaster. - It _ be him. He has gone to Shanghai. - - It _ be Mr. Zhang. He looks like the headmaster. (can) may (can) (can ) (may) (cant) (must) 表示请求、允许、允诺 1. 当对方是决策者时，你代表你（们）自己（I， We），或代表第三者（he,she,they）向对方 （you）请示或提出建议时用： Shall / May (Might) / Can (Could) I / we? Shall he / she / they.? Would / Will you.? Shall we begin our class? 我们开始上课吗？ Shall the driver wait outside? 司机将在外面等 吗？ When shall my father be able to leave hospital? 我父亲什么时候能出院？ Would you do me a favor? 你能帮我一个忙吗 ？ 2. could / might / would 表委婉的功能。如： - Could / Might I use your bike tomorrow morning? - Yes, you can /may. (否定: No, Im afraid not) 不可说：Yes, you could / might. 回答允许时， 用could / might 表委婉是不恰当的。 3. 当你自己（I）是决策者，给对方（you）或第 三者（he，she，they）以命令、警告、允诺 或威胁时，要用shall。此外，当颁布法律、规 定时，也要用shall。如： You shall leave the room at once, and he also shall.( =I order you and him to leave the room at once.) 你马上给我滚出去！他也 一样。（说话者的意志） It has been announced that candidates shall remain in their seats until all the papers have been collected.在所有试卷收上 来之前， 应试者必须留在座位上。（规则或规 定） 4will 可表示意愿、习惯或倾向（否定句中表示 不肯、不能）、在疑问句中表示请求和建议. I will try. She will sit there for hours, waiting for her son to come back. Will you please explain the sentence once more? 题组训练 根据对话内容，选用 can, may, will的正确形式填空。 1- Could you lend me your book? - Certainly, I _. (can) 2- Might I ask you a question? - Surely, you _. (may) 3 - _ you do me a favor? - Of course, I will. (Would) 4 - Dont forget to bring some money on you. - OK, I _. ( wont) 5- Excuse me, but would you like to do it for me? - Yes, I _. A. would B.will C. would like to D.will do 6) “The interest _ be divided into five parts, according to the agreement made by both sides,” declared the judge. A.may B. should C. must D. shall 7） He _ be punished if he disobeys. (shall） 如果他不服从, 就要受到惩罚. 8. We are not going to quarrel at all if you _only let me speak. (will) 只要你让我说话, 我们根本就不会吵架. 9. -Sir, _ he go or stay? -Let him go. A. will B. shall C. might D. could 10. The door _ open. 这门经常打不开. (wont) 11. Ronald _ stay in his small garden for a long time every day in the past. A. could B. might C. should D. would 12.You _ have the book after I read it. 13. (shall) 我看完以后一定把这本书给你. 表示必要性（责任 /义务） 1.must 表示义务, 意为“必须”（主观意志）,表现在和 将来必须做某事用“must+动词原形”，表现在或将 来不必做某事用“dont have todo或dont need todo或neednt do sth”， 例如： We must do everything step by step. 我们一切 都必须循序渐进地做。 -Must we hand in our exercise books now?我 们现在就要交练习本吗？ -No, you neednt. / No, you dont have to. 不必。 neednt have done 表示过去做了某事，但没有做的 必要， 意为“本没必要”。例如： You neednt have waken me up; I dont have to go to work today. . must和 have to must表示主观意志，而have to表示由于客观因素不得不做某事。must没有过 去式，除在间接引语中可用于表示过去时间，在 直接引语中表示过去时间应该用had to代替。 I told her that she must give up smoking. 我 叫她必须戒烟。 We had to get everything ready that night. 我 们那晚得把一切准备就绪。“ 注：must 还可表示“偏要、硬要”，如： - How old are you, madam? - If you must know, Im twice my sons age. 2. should 1) 表义务。意为“应该”（某件事宜于做），用于各 种人称。例如： You should be polite to your teachers. 你对 老师应该有礼貌。 You shouldnt waste any time. 你不应该浪费 时间。 .3、ought to 1) 表义务，意为“应该”（因责任、义务等该做）， 口气比should稍重。例如： You are his father. You ought to take care of him.你是他父亲，应当管他。 You oughtnt to smoke so much. 你不应该抽 这么多烟。 ought to / should have done和 ought not to / shouldnt have done用 于对已发生的情况表示“责备”、“不满” ，分别表示“本应该”和“本不应该” 。例如： With all the work finished, I should have gone to the party last night. You ought not to have made fun of him. He is not the one you laugh at but learn from. 五表示“宁愿做某事”时，可使用下 面这些句式： would rather do sth. would rather do sth. than do sth. would do sth. rather than do sth. would rather sb. did sth prefer to do sth prefer to do sth. rather than do sth prefer doing sth . to doing sth 高考中对这类用法的考查主要侧重结构，因些 要熟记其结构。 题组练习： 根据括号内的中文提示，选用最佳 的情态动词填空： 1We _（必须）report the matter to the boss immediately. 2We _（有必要）to report the matter to the boss immediately. 3 I got up early, but I _（没必要） have done so, because I had nothing to do that morning. 4 It is raining so hard. I _（宁愿） stay at home. 5 If you_（非要）smoke here, do it outside, please. (must) (need) (neednt) (would rather) (must) 6. I cant leave. She told me that I _ stay here until she comes back. (09全国) A. can B. must C. will D. may 7The doctor recommended that you _ swim after eating a large meal. (09浙江) A.wouldnt B. couldnt C. neednt D. shouldnt 8- I dont care what people think. - Well, you _. （09 四川） A. need B. would C. should D. might 9 - Im sorry. I _ at you the other day. - Forget it. I was a bit out of control myself. （08江苏） A. shouldnt shout B. shouldnt have shouted C. mustnt shout D. mustnt have shouted 10- Its the office! So you _ know eating is not allowed here. - Oh, sorry. （2009湖南） A. must B. will C. may D. need 11- Lucy doesnt mind lending you her dictionary. - She _. I ve already borrowed one. （05湖南） A. cant B. mustnt C. neednt D. shouldnt 12 - Could i have a word with you, Mum? - Oh dear, if you _. （06浙江） A. can B. must C.may D. should 13 Some aspects of a pilots job _ be boring, and pilots often _ work at inconvenient hours. （06湖南） A. can; have to B. may; can C. have to; may D. ought to; must 情态动词+have+done” 表“本来” 使用情形分析 1、should have done过去本来应该 （而实际上并没有) should not have done 本不应该 而实际上却已经 ” 如：We should have studied last night, but we went to the concert instead . 我们昨晚本应学习的，但我们却 去看音乐会了。（实际上没有学习） 2、could have done 它表示“过去本来能够“ 实际上没能做。如 I could have run 100 metres in 12 seconds. 我本来能用12秒钟完100米的.（实际上没能） If you could have finished the task in time，you could have been promoted. 如果你当时能如期完成那任务的话，你可能已 提升了（实际上没有被提升） 3、need not have done 它表示过去已做的事，事实上没有必要。如， I need not have got up so early . 我本来不必要那么早起床的（事实上早已起床） I need not have waited for the train for an hour. 我本来不必要等一个小时的火车。 （事实上已经等了一个小时） 问题: would have done 在什么情况下使用呢? 四、would have done 用在虚拟语气中 表示与过去事实相反之假设的结果，常与if 的条件 句连用。 I would have helped you if I had known of your difficulties . 要是我当时知道你们的窘境，我就会帮 助你了（而实际上没有帮助你） If it hadnt rained yesterday, we would have gone out for a walk .假如昨天没下雨，我们就去散步了。（实 际上没有去）。 5 had better have done用于事后的建议，含 有轻微责备的口吻，意为“当时最好做了某事”， 其否定式 表达相反的含义。 You had better have started earlier. You had better not have scolded her. 6 would rather have done表示“当时宁愿做 某事”，其否定式 would rather not have done 表达相反含义，两者都表示“后悔”之意。 I would rather have taken his advice. I raised objections at the meeting, but now I would rather not have done that. Practice 1.Mr White _ at 8:30 for the meeting, but he didnt turn up. A. should have arrived B. should arrive C. should have had arrived D. should be arriving 2. If he had been here yesterday, he _ this pop star. A. would meet B. would have met C. met D. must have met 3.It is hard for me to imagine what I would be doing today if I_ in love at the age of seven with the Melinda Cox Library in my hometown. A. wouldnt have fallen B. had not fallen C. should fall D. were to fall 4. But for the help of my English teacher, I _ the first prize in the English Writing Competition. A. would not win B. would not have won C. would win D. would have won 5. This printer is of good quality. If it _ break down within the first year, we would repair it at our expense.(09天津) A. would B. should C. could D. might 此处should（表示不确定）万一， 用于虚拟语气。相当于were to 例如： If I should see him, Ill tell him. 万一我见到他，我就告诉他。 If it should rain tomorrow, the sports meeting would be postponed. 万一明天下雨,比赛就延期举行。“ 6Thank you for all your hard work last week. I dont think we _ it without you.（08山东） A. can manage B. could have managed C. could manage D. can have managed 7 He paid for a seat, when he _ have entered free.（05山东） A. could B. would C. must D. need 可兼做行为动词的情态动词：need 、 dare 情态动词 (+动词原形)行为动词 . need dare 1.无人称和数的变化; 2.尤其用于： *否定句及疑问句中; *在if/whether之后; *或与hardly, never, no one, nobody连用; 3.常以neednt 和 darent 的形式出现;4.dare有其过去时dared. 多用于肯定句; (sb.) need to do dare to do (sth.) need to be done (sth.) need doing I darent ask her for a rise. 我不敢请求她加薪. How did you dare to tell her that? I wonder whether he dare stand up in public. I dont know how she dares to wear that dress. Do you need any help? I wonder whether he need send it immediately. I need hardly tell you that the work is dangerous. The garden doesnt need watering at the moment. You neednt finish that work today. 判断正误: