情态动词MicrosoftWord文档

1、2013届高一英语备课组编制人：刘春美审核人：杨春乐使用日期：3月中旬4情态动词的用法讲解情态动词有 can /could, may /might, must, have to, shall /should, will /would, dare /dared, need /n eeded, ought to等。情态动词无人称和数的变化；不能单独使用，必须与其后的动词原形构成谓语一、 can/ could1）表示能力（体力、知识、技能）。Eg. 1.Ca n you lift this heavy box?（体力）2. Mary can speak three Ianguages.（知识）3.

2、Can you skate?（技能）此时可与be able to互换，但（1）.be able to有更多的时态。（2）.当表示"经过努力才得以做成 功某事”时应用 be able to,不能用can。Eg.1. I ' ll not be able to come this after noon.2. He was able to go to the party yesterday evening in sp ite of the heavy rain.2）表示请求和允许。Eg. 1.Can I go now?Yes, you can. / No, you can'

3、 t.此时可与may互换。在疑问句中还可用could, might代替，不是过去式，只是语气更委婉，不能用于肯定句和答语中。Could I come to see you tomorrow?Yes, you can. （ No, I' m afraid not.）3）表示客观可能性（客观原因形成的能力）。Eg. 1.They ' ve cha nged the timable, so we can go by bus in stead.2. This hall can hold 500 people at least.4）表示推测（惊讶、怀疑、不相信的态度），用于疑问句、否定句

4、和感叹句中。Eg. 1.Ca n this be true?2. This can ' t be done by him.3. How can this be true?may, mightcan t 或1）表示请求和允许。might比may语气更委婉，而不是过去式。否定回答时可用 must n't，表示"不可以，禁止”。Eg.1. -Might/ May I smoke in this room?No, you mustn' t.2. - May/Might I take this book out of the room?Yes, you can. （No

5、, you can' t / mustn' t.）用May I. ?征询对方许可时比较正式和客气，而用Can I. ?在口语中更常见。2）用于祈使句，表示祝愿。May you succeed!3）表示推测、可能性（不用于疑问句）。might不是过去式，它所表示的可能性比may小。Eg. 1.He may /might be very busy now.2. Your mother may /might not know the truth. must, have tomust n't （禁止，不准），1）表示必须、必要。在回答引出的问句时，如果是否定的，不能用而用 n

6、eed n't, don 'have to （不必）.Eg.Must we hand in our exercise books today?Yes, you must. No, you don ' t have to / you needn' t.2） must是说话人的主观看法，而have to则强调客观需要。must只有一般现在时，have to有更多的时态形式。Eg. 1.The play isn 'tinteresting，and I really must go now.2.I had to work whe n I was your age

7、.3）表示推测、可能性（只用于肯定的陈述句）Eg. 1.You re Tom's good friend, so you must know what he likes best.2. Your mother must be wait ing for you now.4）.表示“一定要；偏要”Eg. 1.Must you worry her with questi on s, just whe n she is busy cook ing dinner?2. Must you make so much no ise?即时练习：1. 那小女孩没有出门。她现在一定在做家庭作业。The gi

8、rl is not out. She2. 路上是湿的。昨晚一定下雨了。The road is wet. It3. 我刚刚拜访过他。他现在一定呆在家里。I have just dropped in on him. He4. 你为什么没有接电话？我当时一定是在睡觉所以没听见。Why didn t you answer my phone call?Well, I , so I didn5. 那男孩想必已经完成了他的家庭作业了。her homework now.last ni ght.at home.t hear it.his homework.The boy四、 dare, n eed1) dare

9、作情态动词用时，常用于疑问句、否定句和条件从句中，过去式为dared。Eg. 1.How dare you say I m unfair?2. He dare n'ts peak En glish before such a crowd, dare he?3. If we dared not go there that day , we couldn 'get the beautiful flowers.2) need作情态动词用时，常用于疑问句、否定句。Eg. 1 . You needn'tcome so early.2. - Need I fin ish the w

10、ork today? Yes, you must. / No, you needn' t.3) dare和need作实义动词用时，有人称、时态和数的变化。在肯定句中，dare后面常接带to的不定式。在疑问句和否定句中，dare后面可接带to或不带to的不定式。而need后面只能接带to的不定式。Eg. 1. I dare to swim across this river.2. He doesn' t dare （to） answer.3. He n eeds to finish his homework today. 即时练习： How dare you say such a

11、 thing?How dare you to say such a thing?f He daren'to speak English before such a crowd, did he?I He daren'tspeak English before such a crowd, dare he?Nobody n eed to be afraid of catch ing the disease.Nobody need be afraid of catching the disease.L These dishes needed be cleaned carefully.T

12、 These dishes need to be cleaned carefully.I These dishes need cleaning carefully五、 shall, shouldShall的用法1）shall用于第一，三人称的疑问句，征求对方的意见或提出建议。Eg. 1.What shall we do this evening?2.Shall I turn on the lights?3.Shall he wait for you outside?2）shall用于第二、三人称，表示说话人给对方的命令、警告、允诺或威胁。Eg. 1. You shall fail if you

13、 don 'work hard.（警告）2. He shall have the book when I finish it.（允诺）3. He shall be pun ished.（威胁）3）shall表示强制，用于法令、条约、规章中，意为“必须，应该”。如：Eg. Can didates shall rema in in their seats un til all the papers have bee n collected. 即时练习：1. Will Mr Wang offer us a hand?Hebe glad to. He n ever refused our re

14、quest.A. canB. mustC. mayD. should2. “ The interestbe divided into five parts, according to the agreement made by both sides.declared the judge.A. mayB. shouldC. mustD. shall3. When can I come for the p hotos? I n eed them tomorrow after noon.D. needTheybe ready by 12 : 00.A. canB. shouldC. might4.I

15、t 'n early seve n o'clock. Jackbe here at any mome nt.D. can八、A. mustB. n eedC. shouldwill, would1）表示请求、建议等，would更委婉。Will / Would you pass me the ball, please?2）表示意志、愿望和决心。1. I will n ever do that aga in.2. They asked him if he would go abroad.3）.will表示现在的习惯，would表示过去的习惯。would表示过去习惯时比 used t

16、o正式，且没有“现已无此习惯”的含义。Eg. 1.Whe n he was a child, he would ofte n go skii ng.2.This old man is stra nge . He will sit for hours without say ing anything.4）.表示意愿Eg.1.She won't le nd me the money .2.This window won t open.5) .will表示某些根据自然规律必定会发生的事情，物体固有的性质，倾向Oil will float on water .七、should, ought t

17、o1) should, ought to表示"应该” ，ought to表示义务或责任，比 should语气重。Eg. 1. I should help her because she is in trouble.2. You ought to take care of the baby.2) 表示劝告、建议和命令。Eg. 1. You should / ought to go to class right away.3) should表推测，语气比较肯定，往往具有一定的客观根据，常译为“理该”When can I come for the p hotos? I n eed them

18、 tomorrow after noon.They should be ready by 12:00.4) 表示“万一”If it should rain tomorrow, don texpect me.5) 表示“竟然”It 'sstra nge that he should be late.八、情态动词+ have done1) can / could + have done有两层含义：1.在肯定句中表示“过去本来可以做而实际上未做某事”，是虚拟语气2.在疑问句或否定句中表示对过去行为的怀疑或不肯定，表示推测。Eg. 1. You could have done better,

19、but you didn t try your best. (虚拟语气)2. He can' t have been to that town.(推测)3. Can he have got the book?(推测)2) may / might + have done 1.表示对过去行为的推测。2.用于虚拟语气中Eg.1. He may not have fini shed the work .2. If we had take n the other road, we might have arrived earlier.想必”。其疑问、3) must + have done用于肯定句中，表示对过去行为的推测。意为“一定、否定形式用can, can' t代替。Eg. 1. You must have see n the film Tita nic.2. He must have bee n to Shan ghai.，其否定式表示某4) should/ought to + have done表示“过去本应该做