高考-情态动词考点课件.ppt

1、Modal Verb Modal Verb 情态动词的语法特征情态动词的语法特征1.情态动词情态动词 不能单独做谓语不能单独做谓语。2.情态动词情态动词没有人称，时态和数的变化没有人称，时态和数的变化，但有些情态动词，如但有些情态动词，如can,may,will,dare也也 有一般式和过去式的变化。有一般式和过去式的变化。Mv Mv 情态动词的个数（情态动词的个数（1515）（4组）组）can/could,may/might,shall/should,will/would（4对）对）have to,had better,ought to,used to（3个）个）must,need,dare

2、考点一：情态动词的基本用法（一）（一）can/could 1.表能够做某事（具备某种能力）；表能够做某事（具备某种能力）；could主要主要 指过去能够指过去能够 Two eyes can see more than one.Could the girl read before she went to school?2.表许可；用于表许可；用于疑问句中表请求疑问句中表请求（could表示的表示的 语气更加委婉）；用于语气更加委婉）；用于否定句中表不允许否定句中表不允许。Can I have a look at your new pen?You cant wear jeans at work.3

3、.表表可能性或推断可能性或推断，多用于否定或疑问句中；，多用于否定或疑问句中；若用于若用于肯定句中表常有的行为和情形肯定句中表常有的行为和情形，意为，意为“有有时会；时而可能时会；时而可能”That cant be Mary-shes in New York.(用于否定句中表某事肯定不真实。)He can be stubborn sometimes.It can be cold here in winter.4.表疑惑或惊讶等情绪；意为表疑惑或惊讶等情绪；意为“究竟能；难道会；究竟能；难道会；到底是到底是”What can they be doing?他们究竟在干些什么？Where can s

4、he have put it?她到底把它放哪了？（二）（二）must1.must 用于用于肯定句肯定句中表说话人的意志或义务；中表说话人的意志或义务；或坚决要求某人做某事；或坚决要求某人做某事；否定否定mustnt 表禁止表禁止 I must go to the bank and get some money.Cars mustnt park in front of the entrance.2.在以在以must 开头的疑问句中，肯定回答用开头的疑问句中，肯定回答用must;否定回答用否定回答用neednt 或或dont have to Must we hand in our exercise

5、 books now?Yes,you must./No,you neednt./No,you dont have to.3.表示可能性或肯定的推断。意为表示可能性或肯定的推断。意为“想必、准是、一定想必、准是、一定”等，只用于肯定句。等，只用于肯定句。He must be ill.He looks so pale.Shes wearing a diamond necklace.She must have a lot of money.4.表说话人生气或不满的情绪，意为表说话人生气或不满的情绪，意为“偏要；非得偏要；非得”-Must you interrupt now?Cant you see

6、Im on the phone?-Sorry,sir,but its urgent.5.用于短语用于短语 if you must(do sth)，表虽然不赞同但可允，表虽然不赞同但可允 许，意为许，意为“如果你一定要的如果你一定要的的话的话”-Can I smoke here?-If you must.（三）（三）will/would 1.表意愿，用于各种人称的陈述句表意愿，用于各种人称的陈述句 I will do anything for you.They wont lend us any more money.2.表请求允许，用于疑问句表请求允许，用于疑问句 Will you send t

7、his letter for me,please?Would you mind leaving me alone for a few minutes?3.表习惯表习惯 She will listen to music,alone in her room,for hours.He would spend hours on the telephone.4.主语为物时，多用于否定句中，意为主语为物时，多用于否定句中，意为“不起作用不起作用”The door wont open.（四）（四）may/might 1.表允许，表允许，might可以指过去时间，也可指现在时间，可以指过去时间，也可指现在时间

8、，语气更委婉。语气更委婉。You may take whatever you like.May(Might)I ask for a photo of your baby?2.表可能（事实上）。表可能（事实上）。might可以指过去时间，也可可以指过去时间，也可以指现在时间，但语气更加不肯定。以指现在时间，但语气更加不肯定。He may be at home,but Im not sure.She may/might not know about it.3.may还可表祝愿还可表祝愿 May you succeed!（五）（五）shall 1.shall用于二、三人称的陈述句，表用于二、三人称的

9、陈述句，表“命令、威胁、命令、威胁、警警 告、强制、允诺、决心告、强制、允诺、决心”等等 You shall do as I day.(命令)You shall have my answer tomorrow.(允诺)Nothing shall stop us from carrying out the plan.(决心)2.shall用于一、三人称的疑问句，表征询意见或请求用于一、三人称的疑问句，表征询意见或请求 允许允许,多与多与I或或we连用连用 What shall we do this weekend?3.shall 常用于主语是第三人称的条约、法律法规、规常用于主语是第三人称的条约

10、、法律法规、规 章制度等文件中表章制度等文件中表“义务义务”或或“规定规定”One of our rules is that every student shall wear school uniform while at school.（六）should1.表义务,意为“应该”（某件事宜做），用于各种人称。You should be polite to your teachers.You shouldnt waste any time.2.表推测，意为“想必一定、照说应该、估计”等。The film should be very good as it is starring first-cl

11、ass actors.They should be home by now.3（表示不确定）万一。If I should see him,Ill tell him.If it should rain tomorrow,the sports meeting would be postponed.4.should 可以用来表示意外；常意为“竟然；居然”I find it astonishing that he should be so rude to you.(七七)ought to 表义务，意为“应该”（因责任、义务等该做），口气比should稍重。You are his father.You

12、ought to take care of him.You oughtnt to smoke so much.（八）used to had better have to1.used to表示过去的习惯动作或状态（现已不复存在）He told us he used to play football when he was young.疑问句:Did you use to go there?/Used you to go there?否定句:I didnt use to go there./I usednt to go there.反意疑问句或简略回答:She used to be very fa

13、t,didnt she?/usednt she?-Did you use to play chess?-Yes,I did.-Used you to get up early in the morning?-Yes,I did./Yes,I used to.双性动词双性动词need,dare,dared 1.need 可以作实义动词或情态动词。可以作实义动词或情态动词。eg:We need to finish the job before dark.You neednt hurry as theres plenty time left.2.dare,dared可以作实义动词或情态动词。可以作实

14、义动词或情态动词。eg:He dared to travel abroad when he was young.How dare you let your little child go out alone?如何分辨是实意动词或情态动词？如何分辨是实意动词或情态动词？有没有加有没有加s；有没有加助动词；有没有加；有没有加助动词；有没有加to；有没有在句首；有没有加有没有在句首；有没有加not；考点二：表推测的情态动词考点二：表推测的情态动词1.对现在或客观事实的肯定的推测对现在或客观事实的肯定的推测Must：肯定；准是；想必是Should：很可能；应该。指按常理推测May/might：也许；大

15、概；表示把握不大的推测Can/could：用于疑问句表怀疑-What are you doing this Saturday?-Im not sure,but I might/may go to the cinema.-Good morning.Ive got an appointment with Miss Smith in the Personnel Department.-Ah,good morning.You _ be Mrs.PetersA.might B.must C.would D.can 2.对现在情况或客观事实的否定推测对现在情况或客观事实的否定推测cant：不可能；推测的语

16、气相当有把握couldnt：也可表不可能；语气较委婉may(might)not:可能不；也许不，表推测的语气不是很有把握It cant be the postman at the door.Its only five oclock.3.对过去情况的推测对过去情况的推测must have done:过去一定做过某事cant have done/couldnt have done:过去不可能做某事can/could have done:过去可能做过某事may/might(not)have done:过去可能（没）做过某事Since nobody gave him any help,he _ hav

17、e done the research on his own.A.can B.must C.would D.need Why are your eyes so red?You _ have slept well last night.A.cant B.mustnt C.neednt D.wont三情态动词+have done 的其他用法should/ought to have done 表过去本该做却没有做 shouldnt/ought not to have done 表过去本不该做却做了could have done 表本可以/本可能做某事却没做 might have done 表本可能但

18、实际没有发生的事 neednt have done 表本来不需要做却做了 He taught us during the lunch breaks and the evening when he should have been asleep.You neednt have taken a taxi,for it was very near to my house.We _ the difficulty together,but why didnt you tell me?A.should face B.might face C.could have faced D.must have done