1、 To learn about the common usage of modal verbs To identify the differences between some pairs of modal verbs by comparison To consolidate the usage of modal verbs through exercises情态动词表示说话人对某一动作或状情态动词表示说话人对某一动作或状态的态度，认为态的态度，认为“可能可能”、“应当应当”、“必要必要”等等，但本身词义不完全，等等，但本身词义不完全，不能单独作谓语，必须和不带不能单独作谓语，必须和不带tot
2、o的动的动词不定式词不定式(ought(ought除外除外) )连用。情态动词连用。情态动词没有人称和数的变化。没有人称和数的变化。 1. can / could 1) 表示能力表示能力 I can swim I can run fast 1. can / could 2) 表客观可能性，表客观可能性，“有时会有时会” An experienced driver can have an accident at times. 1. can / could 3) 表示请求表示请求 Can I go now? Yes ,you can/may 1. can / could 4.表猜测，不相信，怀疑，
3、惊讶表猜测，不相信，怀疑，惊讶 Can this be ture? How can you be so fool？ 凡表示凡表示“经过努力，设法做经过努力，设法做成某事成某事”时，不用时，不用can，须用，须用be able to. The fire spread through the hotel very quickly, but everyone was able to get out.can/could 表示能力表示能力 表客观可能性，表客观可能性，“有时会有时会”表示请求表示请求表猜测，不相信，怀疑，惊讶表猜测，不相信，怀疑，惊讶be able to /can凡表示凡表示“经过努力，
4、设法做成某事经过努力，设法做成某事”时，不时，不用用can，须用，须用be able to.Summary 1 2. may/might 1) 表示许可表示许可 May I use you car. Yes, you may. No, you musnt. 2.may/might 2) 用于祈使句，表祝愿用于祈使句，表祝愿 May you succeed! May you happy! 2. may/might 3) 表推测，可能表推测，可能 He may be busy now. might 可能性小。可能性小。may/might表示许可表示许可用于祈使句，表祝愿用于祈使句，表祝愿3) 表推
5、测，可能表推测，可能may well 很有可能很有可能may as well 不妨，倒不如不妨，倒不如.Summary 2 3.will/ would 1).各种人称表意志，意愿，决各种人称表意志，意愿，决心心 I told her to stop crying ,but she just would not listen. I wanted to your party ,but my mom simply wouldnt let me out so late at night. 甚至在条件句中也可用：甚至在条件句中也可用： If you will allow me, Ill see you
6、home. 3.will/ would 2).第二人称，表请求第二人称，表请求 Will/Would you please keep the door open? 3.will/ would 3).表倾向或习惯，惯于，总表倾向或习惯，惯于，总是是 Fish will die without water. She will sit for hours without saying anything. No matter what you may say, he will always stick to his own views.Whats the matter with the door? I
7、t wont lock. The weather is so cold and the car wont start.就是不就是不would表示表示过去过去的习惯动作或一的习惯动作或一种倾向：种倾向：She would sit like that for hours.Every day he would get up at six and light the fire.He told me the box wouldnt open.will/would1).各种人称表意志，意愿，决心各种人称表意志，意愿，决心2).第二人称，表请求第二人称，表请求3).表倾向或习惯，惯于，总是表倾向或习惯，惯于
8、，总是would表示表示过去过去的习惯动作或一种倾向：的习惯动作或一种倾向：Summary 3 4.should 1).表责任或义务，应该，应表责任或义务，应该，应当当 You should complete your test in time. 4.should 2).表较大可能实现的猜测，推表较大可能实现的猜测，推断，意为断，意为“可能，应该可能，应该” They should be home by now, I think. The street should be crowed at weekends. 4.should 3).表万一表万一 Should I be free tomor
9、row, I will come. 4.should 4).表意外，表意外，“竟然，居然竟然，居然” A gentleman like him should be rude to a lady. should1).表责任或义务，应该，应当表责任或义务，应该，应当2).表较大可能实现的猜测，有理论依据的推表较大可能实现的猜测，有理论依据的推断，意为断，意为“可能，应该可能，应该”3).表万一表万一4).表意外，表意外，“竟然，居然竟然，居然”Summary 4 5.shall 1). shall作为情态动词，用于作为情态动词，用于第二、三人称，表示说话人第二、三人称，表示说话人的意愿，有的意愿，
10、有“命令命令”、“警警告告”、“威胁威胁” “允诺允诺”等意等意思。思。 You shall do as I say. Tell him that he shall have the book tomorrow. You naughty boy! You shall get what you deserve. 2)用在问句中征求对方意见用在问句中征求对方意见和指示，用于第一、第三人和指示，用于第一、第三人称：称： Shall I open the window? What shall they do next?Shall1). shall作为情态动词，用于第二、三人称，表作为情态动词，用于第二
11、、三人称，表示说话人的意愿，有示说话人的意愿，有“命令命令”、“警告警告”、“威威胁胁” “允诺允诺”等意思。等意思。2)用在问句中征求对方意见和指示，用于第一、用在问句中征求对方意见和指示，用于第一、第三人称：第三人称：Summary 5 6.must 1). 必须，应该，否定句：必须，应该，否定句：“禁止禁止” You mustnt park here, for its an emergency exist.Must I be home before eight oclock? Yes, you must. No, you neednt. / No, you dont have to. 6
12、.must 2). 表推测，一定表推测，一定 否定式否定式“cant ,couldnt” There must be a mistake. There cant be a mistake. He must be sleeping at this time . He cant be sleeping at this time . His watch must have stopped. I will go and call him. His watch cant have stopped. It was bought yesterday. 6.must 3). 偏要，非得偏要，非得 If you
13、 must go ,at least wait till the rain stops.在表示在表示“必须必须”这个意思时，这个意思时，must和和have to是很接近的是很接近的但但have to比较强调比较强调客观客观的需要，的需要，must着重说明着重说明主观主观的义务或必的义务或必要；口语中较常用要；口语中较常用have to：must1). 必须，应该，否定句：必须，应该，否定句：“禁止禁止”2). 表推测，一定表推测，一定否定式否定式“cant ,couldnt”3). 偏要，非得偏要，非得have to比较强调比较强调客观客观的需要，的需要，must着重说明着重说明主主观观的义
14、务或必要的义务或必要Summary 67. need可以作情态动词，意为：需要，可以作情态动词，意为：需要，主要用于否定句和疑问句。主要用于否定句和疑问句。Need you go so soon?Yes, I must. No, I neednt. 如果用作如果用作vt 和不定式连用，和不定式连用，可用于各种结构：可用于各种结构： Does he need to know it? This question needs to be discussed. You dont need to do it yourself.need可以作情态动词，意为：需要，主要用于否定句可以作情态动词，意为：需要，
15、主要用于否定句和疑问句。和疑问句。have to比较强调比较强调客观客观的需要，的需要，must着重说明着重说明主主观观的义务或必要的义务或必要Summary 7固定用法固定用法cant too much/enough/more.无论怎样也不过分，无论怎样也不过分， cant help doing情不自禁做某事；情不自禁做某事；may/might as well 不妨不妨may/might well 很有可能很有可能can/could 表示能力表示能力 表客观可能性，表客观可能性，“有时会有时会”表示请求表示请求表猜测，不相信，怀疑，惊讶表猜测，不相信，怀疑，惊讶be able to /can
16、凡表示凡表示“经过努力，设法做成某事经过努力，设法做成某事”时，不时，不用用can，须用，须用be able to.Summary 1may/might表示许可表示许可用于祈使句，表祝愿用于祈使句，表祝愿3) 表推测，可能表推测，可能may well 很有可能很有可能may as well 不妨，倒不如不妨，倒不如.Summary 2will/would1).各种人称表意志，意愿，决心各种人称表意志，意愿，决心2).第二人称，表请求第二人称，表请求3).表倾向或习惯，惯于，总是表倾向或习惯，惯于，总是would表示表示过去过去的习惯动作或一种倾向：的习惯动作或一种倾向：Summary 3sho
17、uld1).表责任或义务，应该，应当表责任或义务，应该，应当2).表较大可能实现的猜测，有理论依据的推表较大可能实现的猜测，有理论依据的推断，意为断，意为“可能，应该可能，应该”3).表万一表万一4).表意外，表意外，“竟然，居然竟然，居然”Summary 4Shall1). shall作为情态动词，用于第二、三人称，表作为情态动词，用于第二、三人称，表示说话人的意愿，有示说话人的意愿，有“命令命令”、“警告警告”、“威威胁胁” “允诺允诺”等意思。等意思。2)用在问句中征求对方意见和指示，用于第一、用在问句中征求对方意见和指示，用于第一、第三人称：第三人称：Summary 5must1).
18、必须，应该，否定句：必须，应该，否定句：“禁止禁止”2). 表推测，一定表推测，一定否定式否定式“cant ,couldnt”3). 偏要，非得偏要，非得have to比较强调比较强调客观客观的需要，的需要，must着重说明着重说明主主观观的义务或必要的义务或必要Summary 6need可以作情态动词，意为：需要，主要用于否定句可以作情态动词，意为：需要，主要用于否定句和疑问句。和疑问句。have to比较强调比较强调客观客观的需要，的需要，must着重说明着重说明主主观观的义务或必要的义务或必要Summary 7practice He _ speak English fluently. 2
19、. Rose _ cook meals for herself two years ago.3. He _swim across the river before the ship sank.4.It _ be very cold in Siyang in winter.5.-Could I use your pen? (语气委婉语气委婉)-Yes, you _. 6.The boss said to the secretary, “ If you work well, you _ have a rise.”cancouldwas able to cancanshallpractice7.Th
20、e train leaves at 7 oclock. I _go now.8.-Must you go home now?- No, I _.9. I have told you many times. _ you speak in class?10. _ you be happy!11.It is strange that it _ be so hot today.12. We _ thank you too much for what youve done for us. mustdont have toMustMayshouldcantpractice13. Its too late.
21、 You _ as well not go.14. He _ be tired after driving a day.15. Someone is knocking at the door. Who _ it be?16. The guest is waiting outside. _ he come in ?17.The school rules say that no child _ be allowed to leave the school during the day.18. Why _ you find another job while you have got one?mig
22、htmustcanShallshallmust must have done could have done cant /couldnt have done may /might have done should/ought to have done neednt have done We could have faced the difficulty together, but why didnt you tell me. Harry is feeling uncomfortable. He must have drunk too much at the party last night.
23、Sorry, I am late. I might have turned off the alarm clock and gone back to sleep again.must have done He must be a student , _? He must have stayed up late ,_. He must have stayed up late last night?_.isnt he ?hasnt he ?didnt he ?must have done must have done 的否定式的否定式: cant /could have done You _ no
24、t have seen him in the street yesterday, for he has been to Japan.can/couldcould have done I could have come on time, but my car broke on the way. -Happy birthday -Thank you! Its the best present I could have wished for.may/might have done Sorry, I am late. I might have turned off the alarm clock an
25、d gone back to sleep againshould(not)/ought (not)to have done I shouldnt have scolded her for such a small thing.need (not) have done You neednt have walked so quickly since time was enough. abilityHe can touch his toes with his mouth. No one thought he could pass the exam.Although the dictation was
26、 very hard yesterday, we were able to pass it.can / could / be able to obligationought to/should have to mustadvisability值得推荐值得推荐necessity必要必要 certaintymight may could should ought to will must very uncertainalmost certaincan could may might permissioninformal / spokenformal / written一、虚拟语气在条件状语从句中的
27、用法一、虚拟语气在条件状语从句中的用法条件从句条件从句 If 从句的谓语形式从句的谓语形式主句的谓语形式现在过去未来did / werehad donewould/could/should/might +V.(原原)would/could/should/might+have+p.p.1. did / were2. should do 3. were to dowould/could/should /might + V.(原原)假设条件虚拟倒装假设条件虚拟倒装. 条件从句中条件从句中有有should, were, had三个助动三个助动词时词时, 可以把可以把if省略，并将这三省略，并将这三个词
28、提至句首。个词提至句首。 If I were you, I would give it up. If it were not for your advice, we couldnt have got over the difficulties. I you, I would give it up. it not for your advice, we couldnt have got over the difficulties.If I had had time, I would have run round that lake again.If there should be a flood
29、, what should we do? I had time, I would have run round that lake again. there be a flood, what should we do? 虚拟语气在假设条件句型注意点：虚拟语气在假设条件句型注意点： 1.假设条件从句谓语动词发生的时间与主句所假设条件从句谓语动词发生的时间与主句所假设的谓语动词不一致，叫做错综条件虚拟假设的谓语动词不一致，叫做错综条件虚拟语气。主句和从句的谓语动词要依照假设的语气。主句和从句的谓语动词要依照假设的时间而定。时间而定。 If you my advice just now, you b
30、etter now. If you hard before, you a college student now.had followed would be had studied would be If you had gone to bed earlier last night, you _(be) so sleepy now.would be If you _ (attend) the meeting yesterday, you _ (know) what we are doing now.had attendedwould knowIf it _ (be) not for the f
31、act that his father is the manager, he _ ( not get) the position.would not have gotwere含蓄条件句含蓄条件句I was busy that day. Otherwise I would have gone there with them.If I hadnt been busy that day, I would have gone there with them.I would have finished the work, but I have been ill.If I hadnt been ill,
32、I would have finished the work.Without air, there would be no living things.If there were no air, there would be no living things.But for your help, I couldnt have done it.If it hadnt been for your help, I couldnt have done it.3.含蓄虚拟语气含蓄虚拟语气: :用介词短语代用介词短语代替条件句。替条件句。常用的介词有常用的介词有with, without, but for
33、等等 He was busy, he_ (come). He _(come), he is very busy now. I should have helped him, I _(out). would have come would come was out 二、虚拟语气特殊句型：二、虚拟语气特殊句型： wish + 宾语从句现在：现在：过去：过去：未来未来：过去时过去时 (did/were)过去完成时过去完成时 (had done)would/could/might+V. should I wish I were a bird. (现在现在) I wish I hadnt made su
34、ch a mistake. (过去过去) We wish our parents wouldnt punish us. (未来未来)2. If only = How I wish thatIf only I his name!If only we your advice!If only I him again!3. would rather that -现在：现在：过去：过去：未来：未来： I would rather you paid me now. (现在现在) I would rather you had gone, too. (过去过去) Dont come. I would rath
35、er you came tomorrow. (未来未来)过去时过去时过去时过去时过去完成时过去完成时4. as if /though + 从句从句现在：过去：过去时过去时过去完成时过去完成时 He looks as if he . They talked as if they for years. She loves the baby as if it her own son. It seems as if it spring. I remember the whole thing as if it yesterday.5.Its (about/high) time +that -should
36、 +V.过去时过去时你该走了。你该走了。Its high time that you went.Its high time that you should go.6. 表示要求，命令，建议的虚拟语表示要求，命令，建议的虚拟语气。气。1). 宾语从句。常见动词：宾语从句。常见动词：: : order, command : : 2). 主语从句。主语从句。以上动词相应的名词构成的名词性从句以上动词相应的名词构成的名词性从句( (包括主语从句，表语从句和同位语包括主语从句，表语从句和同位语) )也也要使用虚拟语气。从句中的动词形式一要使用虚拟语气。从句中的动词形式一样。样。 order, advic
37、e, suggestion, proposal, demand, request, desire Its suggested that the plan (should) be carried out. My demand is that she (should) come to see me once a week. All of us are for the advice that the chemical factory (should) be closed down.主语从句主语从句 表语从句表语从句 同位语从句同位语从句 7. Its necessary /strange/ natu
38、ral/ important + that It is important that we ( should ) master a foreign language. It is strange that she to come to the party. Its necessary that we hard.8. 意义上面有虚拟意义上面有虚拟Take your money that you (should) need it.We hid the money (以免以免) it (should) be stolen.He works very hard he (should) fail.9. 某些简单句的固定句型：某些简单句的固定句型： Heaven him! God you! May you ! Long the Peoples Republic of China!
