1、高一英语语法5情态动词高一英语语法（5）：情态动词一、情态动词的特征1. 本身有词义；2. 情态动词+V原=谓语；3. 不随人称和数的变化。二、情态动词的种类肯定式否定式疑问式can /can + 主语 + V原could /maymight /will /would /shall /should /ought to /must /have / has / had to /need /dare /三、情态动词的基本意义及用法1. can / could1）能力现在“能够；会”I can swim now. 翻译：过去“能够；会”He could swim at the age of 5.翻译：
2、肯定句can + V原could + V原2）不能够现在“不能够；不会”I still cant swim now. 翻译：过去“不能够；不会”He couldnt swim at the age of 5. 翻译：否定句cannot / cant + V原could not / couldnt + V原3）客观的可能性现在“可能”Accident can happen to any drunken driver.翻译：过去“可能”He said that an accident could happen at anytime. 翻译：肯定句can + V原could + V原4) 怀疑现在“
3、不可能”He cant be a boss. 翻译：过去“不可能”He couldnt leave, for his bad was still here. 翻译：用于否定句cant + V原couldnt + V原5）请求；允许“可以吗？”A: Can I have a look at your new design?1 B: Yes, of couse you can. 2 B: No, Im afraid not. 翻译：“可以吗？”（更委婉）A: Could you please help me with this funiture?1 B: Yes, I can. 2 B: No,
4、Im afraid not. 翻译：1 一般疑问句2 注意回答Can + 主语 + V原？Could + 主语 + V原？4）惊异现在“怎么能？”How can you believe such a liar like him? 翻译：过去“怎么能？How could you believe such a liar like him at that time? 翻译：疑问句How can + 主语 + V原？How could + 主语 + V原？2. may / might1) 可能性的推测现在“可能；也许”Mary may visit me today.1 过去“可能；也许”2 更委婉I
5、told my mother that Mary might visit me.I must go home at once. Mary might visit me.肯定句may + V原might + V原2）可能性的推测现在“可能不；也许不”It may not rain today1 过去“可能不；也许不”2 更委婉She said it might not rain that day.It might not rain today.否定句may not + V原might not + V原3) 请求允许“能不能？”My I trouble you to pass me the boo
6、k?“能不能”（更委婉）Might I trouble you to pass me the book?1 一般疑问句2 比can和could的语气弱May +主语 + V原?Might +主语 + V原?4）允许；许可“能够吗？A: May I listen to music while doing homework?1 B: Yes, you can. / Yes, you may2 B: No, you musnt. / No, you cannot. / No, you may not. / No, you had better not. / No, Im afraid not.1 一
7、般疑问句2 注意回答May + 主语 + V原?5）祝愿祝你May you have a happy life!祈使句May you + V原3. will / would1）意志；意愿现在“愿意”I will tell you about it.过去“愿意”He said that he would tell you about it.肯定句will + V原would + V原2) 请求、建议“好吗？要不要”1 Will you close the window?2 Wont you drink some more coffee?“好吗？要不要？（更委婉）Would you come th
8、is way, please?1 第二人称2 一般疑问句1 Will you + V原2 Wont you + V原Would you + V原3）习惯性动作现在“惯于，会”This old woman is strange. She will sit for hours without saying anything. 过去“惯于”This old woman was strange. She would sit for hours without saying anything.肯定句will + V原would + V原4) 预料；猜想将来“大概会”It will be about te
9、n when he gets home.过去“大概会”It would be ten when he left home.肯定句will + V原would + V原5) 规律性将来“注定会”People will die without air.过去“注定会”He said that his lovely dog would be lonely if he didnt accompany it.肯定句will + V原would + V原4. shall1）征求对方意见；向对方请示“可以吗？；好吗？”Shall Peter go there with us tomorrow?Shall I
10、get you some tea?Shall the boy wait outside?1 疑问句2 第一人称；第三人称Shall + I, we; it, he, she, they + V原？2）允诺；命令；决心；警告；威胁“会；务必；”You shall get an answer from me by this weekend. (允诺)You shall be sorry for it one day, I tell you.（警告）Each citizen shall carry his ID card when travlling. (务必；规定)1 陈述句2 第二人称；第三人称
11、you; it, he, she, they + shall + V原.5. should1）劝告；建议“应该”I think we should study English hard.从道义上“应该”should + V原2）推测“可能；应该；准是”It should be Mary who has taken all the books on the desk.should + V原3）谦逊；客气；委婉“依我/我们看，”You are mistaken, I should say.第一人称I should say; We should say4）不能理解；感到意外、惊异“竟会；怎么会”Wh
12、y should you be so early today?疑问句why / how should + 主语 + V原6. ought to1）劝告；建议“应该”试比较：You are his father and _ take care of him.Young people _ show respect to the old.(should, ought to)1 与should意义大体相同2 语气重于should3 从法律上“应该”ought to + V原2）推测“可能；应该；准是”She ought to get to Beijing by now.与should意义大体相同oug
13、ht to + V原7. must 1）必须“必须”I told her that she must give up somking.1 语气比should，ought to强烈； 肯定句； 主观意识must + V原2）严禁“不准，不应该，禁止”Drivers mustnt drive after drinking.否定句mustnt + V原3）对现在有把握的推测“一定，准是”You must be ill. I can see it from your face.He must be doing his work now, for the light in his office is o
14、n.肯定句must be4) 偏执；固执“为什么非要”Why must you always interrupt me?疑问句Why must + 主语 + V原？*在回答带有must的问句时，肯定回答：Yes, must； 否定回答： No, neednt. No, dont have to.如：A: Must I finish my homework before eight?B: Yes, _.B: No, _. / No, _8. have to / have got to1）必须“必须；不得不”I have to / have got to hand in my term paper
15、 before 5:00 pm today.1 肯定句2 由于客观因素不得不做某事1 have to + V原2 have got to + V原2）不必要“不必”Drivers mustnt drive after drinking.否定句dont have to + V原havent got to + V原You dont have to tell him about it.Im glad I havent got to work today.9. need1) 需要，必要“需要吗？有必要吗？”A: Need I tell him everything thats happened to
16、his parents?1 B: Yes, you must.2 B: No, you neednt.1 情态动词2 否定句；疑问句3 没有数的变化；没有时态的变化4 注意回答Need + 主语 + V原？主语 + neednt + V原？2）需要，必要“需要；有必要”I need to go to Beijing this Sunday to attend a book fair（书展）.He needs to; He said that he needed toI dont need to leave at once.He doesnt need to; He said that he d
17、idnt need toA: Do you need to have a rest?1 B: Yes, I do.2 B: No, I dont. 1 实义动词2 肯定句；否定句；疑问句3 有数的变化；有时态的变化4 注意回答肯定句：主语 + need / needs / needed + to do否定句：主语 + dont / doesnt / didnt need + to do疑问句：do / does / did + 主语 + need + to do10. dare1) 敢；敢于“敢于吗？胆敢吗？”A: Dare he tell them what he knows?1 B: Ye
18、s, he dare.2 B: No, he darent.1 情态动词； 否定句；疑问句；3 没有数的变化；没有时态的变化；4 注意回答Dare + 主语 + V原？主语 + darent + V原？2）敢；敢于“敢于；胆敢”I suppose that he dares to tell the manager the truth.I dont dare to tell him the truth.A: Do you dare to jump down from here?1 B: Yes, I do.2 B: No, I dont. 1 实义动词；2 肯定句；否定句；疑问句；3 有数的变化
19、；有时态的变化4 注意回答肯定句：主语 + dare / dares / dared + to do否定句：主语 + dont / doesnt / didnt dare + to do疑问句：do / does / did + 主语 + dare + to do3) 习惯用法 大概；我想；我估计 I dare say, You are tired, I dare say.I dare say youve spent all your money by now. 你胆子好大啊！How dare you！4）过去“不敢”；过去“敢不敢”？过去“不敢”；过去“敢不敢”？A: Dare you ha
20、ve done it yesterday?B: I darent have done it yesterday, but I think I dare now.否定句；疑问句；whether之后darent have done; dare + 主语 + have done?四、情态动词后动词的时态形式1. 一般式：“情态动词 + V原”，表示情态动词的基本含义。（如上）2. 进行式：“情态动词 + be + doing”，表示对现在或将来正在进行的行为进行推测，意为“或许正在，应当正在，想必正在，准是正在”（may / might / should / ought to / must be d
21、oing语气由弱到强）如：1) He might be sleeping next door. Lets not disturb him.2) She ought to be waiting for us. She promised to.3) He must be doing his work now, for the light in his office is on. 3. 完成式：“情态动词 + have + done”may have done可能已经He may have finished his work, or he didnt have any chance to play
22、with other boys.may not have 可能没有He may not have finished his work, or he could go out with his friends.might have done1 可能已经（委婉）He might have finished his work, or he didnt have any chance to play with other boys. 本可以You might have given him some advice.mightnt have done 可能没有He might not have finis
23、hed his work, or he could go out with his friends. 本不能Without your help, he mightnt have finished his work alone.can have done可能已经The room is so clear; it can have been cleaned.cant have done不可能已经The room is in a terrible mess; it cant have been cleaned.could have done1 可能已经（委婉）The room is so clear;
24、 it could have been cleaned. 本可以I could have got up early if the clock were not broken.couldnt have done 不可能已经The room is in a terrible mess; it couldnt have been cleaned. 本不该You couldnt have told the news to your father.should have done / ought to have done本应该I should have gone just now if there we
25、re no rain.shouldnt have done / oughtnt to have done本不应该They shouldnt have given him so much money only because he asked for.must have done一定已经It must have rained, for it is wet outside.neednt have done其实不必You neednt have come yesterday .五、常用情态动词的用法比较1. cant：不可能，一定不；may not：可能不，或许不2. must：主观看法；have
26、to：客观需要3. mustnt：决不能；dont have to = neednt：不必4. can与be able to1) be able to比can相比有更多的时态。如： _ you _ _ _ camera（录制） the lecture tomorrow? Im sorry I _ _ _ _ answer your letter in time. 真对不起，我没能及时给你回信。2) 在过去时态中，could仅指具备某种能力，但实施结果如何不明确；而was / were able to不仅仅说明有某种能力，而且成功地做到了，相当于manage to do或succeed in d
27、oing，译为“成功地”。如：1 Yesterday I was able to get home before the heavy rain.2 He was able to flee Europe before the war broke out.3) 在否定句中或与感官动词连用时，could / was were able to可以通用。如： He hurt his leg and couldnt be / wasnt be able to play football. I could / was able to smell something strange.六、情态动词其他的搭配用法
28、1. can but + V原：只好，至多不过；如：We can but do our best.2. cannot help but + V原 = cannot help doing不得不，不能避免，不禁。如：1) The girl couldt help but live on herself.2) When I try to spea, I cant help making mistakes.3. cannot + V原 + too + adj. / adv.原级 = can never + V原 + too + adj. / adv.原级：无论怎样都不过分，越越好。如：We cant thank you too much for what youve done for us.4. may / might + V原 + but + 句子：我承认是事实，但是。如：He may have lived here for years, but he has very few friends here.5. may / might as well + V原=had better + V原还是的好。如：Its too late. You
