15.第十五章 助动词(81-85).doc

15.第十五章 助动词（81-85）一. 助动词的特征1. 助动词后面要接原形动词。 He can speak English. (Right) He can speaks English.(false)2. 现在式中主词为第二人称单数，字尾不加S。He can speak English.3. 形成否定句时，在助动词后面加not. He doesnt speak English. Or He cannot speak English.4. 形成疑问句时，将助动词放在主词的前面。 Can he speak English? Or does he speak English? 5. 两个助动词不能连用。 You will can swim soon. (错)You will be able to swim very soon.二.助动词的用法(1) Can (could) 表示“能力，许可，可能”A:表示“有能力的”(be able to) 形容词有能力的。1. He can speak Japanese, but he cannot write it. (只有can可以和not 在不简写的情况下，连在一起。)2. She tried to tie the rope, but she couldnt.(过去式)3. Tomorrow, I will be able to finish the paper and go out to see the exhibition. 助动词是will只能用一个助动词，所以要用be able to. 加上助动词后面必须接原形动词，所以是be.4. 我一直都想不起他的名字。I havent been able to recall his name. (have 是准助动词)Have +not+P.P. (现在完成式)+ beV able to = Have+not+been able toB： 表“可能“1. It cannot be true. （true形容词,be 动词可以形容在一起表示状态。 Be 动词和形容词都可以表示状态。）Cannot+Vr+ Be true = Cannot be true. 2. This kind of thing can happen every now and then.3. A quarrel can sometimes cause trouble. (sometimes 是频率副词（偶尔的），他可以放在be 动词和助动词之后)4. The light in the sky could be a UFO. C. 表示”许可”。1. You can come in if you have a ticket.2. Im afraid (that) you cant park your car here.3. Can I leave early because Im not well today? - Certainly.D. 表示”请求”。1. Can you do me a favor? (Could是用在自己，对自己客气也可对晚辈，但不可以对长辈说could you.直接说 can you.) Could I come in? 比Can I come in? 较客气。 这里的could 不是can 的过去式。2. Could you please repeat your cell phone number please?(2) May (might) A表示“许可“1. You may not chew gum in class.2. May I interrupt you? Sure.3. Might I come in? 表示更加客气，但是表示可能性的时候用might 比may 表达更客气.B 表“可能“1. You may be right but I am against your opinion. 助动词+Be+形容词2. His health may or may not turn for the better.3. She might not know that you are in here. (这里的might 指的是婉转的意思。)C 表“祈愿”1. May I never see a light like that again? （sightseeing 观光）2. May you succeed! (success 名词； successful 形容词；succeed 动词)(3) MUST A表“义务；命令。” 1. You must return the book by next Tuesday.2. You must not talk with your month full. (你吃东西的时候不要说话，介词with 的中文解释是伴随着附带的状况)(must 是必须的意思，must not 是不可以的意思， must 和 not 没有缩写,must 不可以用在否定句中。)3. Must I really attend the meeting?- Yes, you must. （是的，你必须去）- No. You need not. （不，可以不去）- No. You dont have to.重点：must 本身没有过去式must= have to 其过去式是had to ; 未来式是 will have to 必须的完成式 have had to Have P.P. 完成式 Have to 必须= Have had to.1. I had to go to see the doctor because I caught a cold. / I caught Toms cold. 被Tom 传染2. You will have to replace this light bulb. 3. 我们必须一直呆在这里，因为外面正下着大雨。必须一直说明是必须完成式We have had to stay here because its raining heavily. (Heavily= cats and dogs)重点: 口语中,常用have got to 代替have to+ vr.1. Youve got to be more patient, Mary. Have to do something.当have 为助动词的时候可有和主词缩写，当一般动词的时候不可以。B. 表“推测”。1. You must be kidding.2. That is an enormous animal; it must weight a ton. 重点：表“推测”没有否定的时侯用must,其否定用 cannot 代替。1. Shes very young, she cannot be over twenty. (表示推测)It cannot be true. Or cant be. 不可能C. 表“必然” All men must die. 人类难免一死。(4) Will Will 最基本的概念表示未来式(未来即将要走的事情)A. 表示“现在的推测” (对现在的推测)1. Mom will be downstairs now. （妈妈现在可能在楼下哟。）will 表示是对现在的推测2. That will be his house. (那将是他的房子吧。)B. 表示“主词强烈的意志; 固执”1. The window will not open. (主动表现)2. He will insist on his right.C. 表示“习惯; 倾向”1. Accidents will happen.2. A drowning man will catch at a straw. (一个无路可走的人，能看到一丝希望都觉得是好事。)D. 表示“请求，劝诱”1. Will you bring me a ladder? Please2. Will you have one more coffee? (带是bring, 带走是take , 取:fetch)(5) WouldA. 表示“客气的请求”。1. 你介意我坐在你旁边吗？ 1. Mind+Ving 2. 也可以用if 子句 Would you mind if I sit next to you? If 子句。你介意我坐（2 个主词2个动词，要用连接词if）Would you mind me sitting next to you? (mind是动词，动词后面遇到人称代名词用受格。)Would you mind my sitting next to you? (sitting 是动名词，动名词可以当名词使用，名词前面用所有格。)2.请你稍候再打给我好吗？Would you please call me back later? B: 表示“过去的习惯” 常伴随着sometimes, often等。1. Before they had TV, people would listen to the radio. （would 指的是过去的含义）2. Susan would often chat with us at this coffee shop. （would 指的是过去的含义）C. 表“过去的意志”。 *如果will指现在的意志,would就指过去的意志*1. You wouldnt eat carrots when you were a boy. (当你是小男孩儿的时候，你是不吃胡萝卜的。)2. The rusty screw wouldnt come loose. (Screw driver 螺丝启子) （rusty 生锈的）(6) used to+ 原形动词A: 表示“过去习惯”。1. John 以前在下课后常到餐厅打工。John used to work part-time at a restaurant after school.2. 我以前常在午休时去游泳，但现在则不。I used to go for a swim on lunch break, but now I dont. 3. I used to go to work the movies every Sunday when I was young. = I would often go to the movies when I was young.注意： used to 是表示过去相当长时间的习惯。Would 是表示过去动作的重复，其习惯的意味淡重点： used to 的否定： Used not to / didnt use toused to 的疑问： Used+S+to? Did+ S+ use to1. He used not to drink. = He didnt used to drink. （在西方喝汤是eat soup）2. 他以前常和你一起去上学吗？Used HE to go school with you? *Used+S+to?= Did he used to go to school with you?3. We used to talk about our future, usednt we? 附加问句（附加问句否定要和not缩写）, didnt we?B: 表示“过去持续的状态” used to be 可以指状态。Be 表示状态1. 从前这里有一座古庙。 There used to be an old temple here.2. 他不再是3年前的他了。 He isnt what he used to be. (used to be 过去的状态)重点：What+某人+Be动词表示某人的什么时候的自己。What I am.现在的我 What he was过去的他重点：物 be used to V = (物)被用来 例如: The knife is used to cut bread. (use 使用) to cut 表示目的人be used to Ving = (人)习惯(现在的习惯,这里的to 是介词的to , Im used to keeping good hours.人 used to V = 过去习惯于（过去的习惯）(7) Should A. 表示“义务”1. 你应该多运动并且少吃东西。You should exercise more and eat less.2. 政府应该多花钱在教育上面。The Government should spend more money on education.(Spend 指某人花费多少；take 多指花费某人多少时间；cost 某人花钱在物品上的费用)(exercise 当名词take more exercise. Exercise 当动词 exercise more)B.表示“推测”。1. 我们的客人应该在一个小时内会到吧。Our guests should be here within an hour.2. 我昨天寄电子邮件给你，所以你应该知道邀请函的事吧。I sent you e-mail yesterday, so you should know about the invitation.C.表示“强烈的惊奇”- 怎么会的意思1. Who should make such a foolish mistake? 谁会做这么愚蠢的错误呢？2. How should I know it? 我怎么会知道这件事？意思是我不知道这件事。注意: ought to 的语气比should较强，在口语中更常用。另外 should, ought to, be supposed to 都表示应该的意思。 I do not know what I am supposed to think. 我不知道我应该怎么想。1. 我的脚踏车应该在这里，因为我就把它停在电线杆旁。My bike should/ought to/was supposed to be here, because I left it just beside the telegraph pole. 2. You oughtnt (to) do so.3. Ought we (to) tell him about it?在美式英语中，ought 后面的 to 在否定和疑问句中可以省略。(8) need (需要) Need可以当动词Need可以当助动词（当need当助动词来用的时候只用在否定句；疑问句）*I like swimming/ I like to swim. *I enjoy swimming. I want to swim.Need 当动词：如果主词是: 人+need+to V. 如果主词是: 物+need(s)+Ving/ to be P.P. （to be P.P.是不定词的被动）You dont need to speak to loud, I hear you very well. = You need not speak so loud, I hear you very well. (当助动词直接加not )2.我需要把节目录下来吗？ 不，你不需要。Do I need to record the program on the tape? No, you dont (need to)Need I record the program on the tape?No, you neednt. / Yes, you must.(need 如果当助动词，只能用在否定句和疑问句中)(9) Dare Dare 的过去式dared, dare 也用动词用法，形成dare (to)+原形动词1. 她不敢说实话。She dare not (darent) tell the truth. / She doesnt dare to tell the truth.2. 那时我不敢嘲笑他。I dared not laugh at him at that time. = I didnt dare (to) laugh at him at that time.3. How dare you ask me for help?4. I dare say he is right.三. 含助动词的惯用表现(1) 含助动词+have+过去分词 (重要内容)1. You may have heard this joke before.2. The keys might have fallen out of your pocket.3. I must have been asleep. I didnt hear your footsteps. Have + P.P. 表示过去睡着。表示推测可能性大小的排列- mustmaymight.4. He cannot have survived in the accident.5. You should/ought to have applied for the job sooner.Should have+P.P. 含有“责备”的含义，表示“应该去做 ; 但实际上没有做。”You should have come to my party last night.6. She need not have come so early. 说明她早就来了。She has come here.(2) 含can 的惯用表现1. cannot help+ving (禁不住做某事 ) I cannot help crying whenever I hear that song.2.Cannot help that but V (不能不 ) I cannot help but think so. (我不得不这么想。)3. cannot too (无论再 ； 也不为过 ) You cannot be too careful when you choose a husband.(3) 含may (might) 的惯用表现1. May well+ V. (太可，恐怕是 ) He may well say so.She may well be lost; she has a poor sense of direction. 她恐怕是迷路了。A sense of humor.2. May (might) as well+ V (不妨 )Youll never solve that problem. You might as well give up.3. May (might) as well V as V (与其 不如 )You might as well throw your money into the sea as lend it to him.第一个动词解释为不如; 第二个动词解释为与其 与其把钱借给他不如把前丢进海里。(4