人教版高一英语英语必修3Unit1语法情态动词

1、Modal Verb I 情态动词,Unit 1 Grammar,情态动词表示说话人的某种感情或 语气，对某一动作或状态的某种态度。表示“需要、可以、必须、应当”等。,什么是情态动词？ (Modal Verbs),Underline the modal verbs,Most ancient festivals would celebrate the end of cold weather. It is now a childrens festival, when they can dress up If the neighbors do not give any sweets, the chi

2、ldren might play a trick on them.,6/30/2020,4,Underline the modal verbs,In European countries, people will usually decorate churches She would never forget him. At the Spring Festival in China, people may give children lucky money in red paper.,情态动词的语法特征,1. 情态动词不能单独做谓语,后接动词原形。（除ought to; have to外）,2

3、. 情态动词没有人称，数的变化，但有 些情态动词（如can, will）有一般式 和过去式的变化。,6/30/2020,6,Modal Verb I,may/might can/could will/would shall/should must/cant,can的主要用法是： 1. 表示能力： eg. The girl can dance very well. 2. 表示说话者的推测事物的可能性: eg. Can the news be true? 3. 在口语中, 表示请求或允许： eg. Can I sit here?,can和could,could的主要用法： 1. could -ca

4、n的过去式, 表示与过去 有关的能力或推测: eg. I can speak fluent English now , but I couldnt last year.,2. could可以代替can表示请求, 但语气较can客气、委婉: eg. Could you lend me your dictionary? Could I use your bike? 用could 提问，答语用can （即：could 不能用于现在时态的答语中） -Could I borrow your pen? -yes, you can.,can和be able to辨析 can(could)和be able t

5、o都可以表示能力，意思上没有区别。但can只有现在式和过去式，而be able to则有更多的形式。如： Those bags look really heavy, are you sure youll be able to carry them on your own?,may和might,may 的用法： 1. 表示请求、允许（比can较为正式） eg. May I come in ? You may go now. 用may 提问，否定回答用 must not (mustnt) 禁止、阻止 had better not 最好别 may not 不可以,6/30/2020,12,May I

6、 smoke here? Yes, you may. No, you mustnt No, youd better not. No, you may not.,2. 表示说话人的猜测（肯定句和否定句） 含有“也许”“大概” “可能”之意。 My friend may arrive this afternoon. 3. 表示祝愿; 但语气较正式: eg. May you succeed! May you have a good journey!,6/30/2020,14,might 的用法,may 的过去时，表示可能性时，语气显得更加不确定。 My friend might arrive thi

7、s afternoon.,will和would,Question: will/would 是助动词还是情态动词？ will 构成将来时-助动词。 表示“意志”“决心”“请求”-情态动词。 例： I will tell you something important. 我要告诉你一件重要的事情。（助动词） Will you tell her that Im here? 请您告诉她说我在这儿，好吗？（情态动词）,will 和 would的用法,1、表示请求、建议等，用于第二人称 （用would比will委婉） Will you please take a message for him? Woul

8、d you please tell me your telephone number?,2.表示习惯或倾向， 意为“总是”，“习惯于”。 eg: Fish will die without water. People will talk. (人们总会说闲话。) When we worked in the same office, we would often have coffee together.,shall和should,shall 用法 表征求意见，用于一、三人称 ， （疑问句） Shall we go by train, Mom? Shall he attend the meetin

9、g?,shall和should,shall 用法 2.用于二 、三人称 的陈述句中，表威胁、警告、命令、允诺等语气 He shall be sorry for it one day, I tell you. You shall do as I say. If your children dont do as I tell you, you shall not go to the party.,（警告）,(命令),(威胁),should 用法 应该=ought to （劝告、建议） You should study hard. You should read his new book. 2. 表

10、估计，可译为“按理应当”、“估计”。 Try phoning Robert, he should be home now.,should 用法 3. 用于第一人称，询问意愿，语气温和委婉 Should I trust him? What should I do now? 4. 万一，用在if引导的条件句中，表示一件事听起来可能性很小，但也不是完全不可能。或直接用于句首。 If I should be free tomorrow, Ill come. Should I be free tomorrow, Ill come.,should 用法 5. “居然”，“竟然”,表说话人意料之外。 To

11、my surprise, he should be a thief. Why should everyone want to marry Tony?,must的主要用法,1. 必须，应该。 语气比should，ought to 强烈。 eg: Everybody must obey the law. You mustnt drive so fast in the street. 2. 表示有把握的猜测。“一定”、“准是”结构：must be eg: He must be an honest boy.,用must 提问，回答方式 肯定回答：yes, please / Im afraid so 否

12、定回答 ：neednt / dont have to -Must I come back before ten? -No， you neednt. 表猜测的否定或疑问句用can/could,不用mustnt. If Mary didnt leave here until 5:00, she cant be home yet.,-_ I go out to play, mum? -No, you_. You should do your homework first. A. Might; wouldnt B. May; had better not C. Must; mustnt D. Need

13、; mustnt,Exercise,2. -Where is Emma? -I cant say for sure where she is, but she_ be out shopping. A. can B. should C. must D. may,3. The room is in a terrible mess; it _ cleaned. A. cant have been B. couldnt be C. may have been D. would be,4. There _ be any difficulty about passing the road test sin

14、ce you have practised a lot in the driving school. A. mustnt B. shant C. shouldnt D. neednt,1 Children under 12 years of age in that country _ be under adult supervision when in a public library. (2004 上海） A. must B. may C. can D. need,直击高考,2 Whats the name？ Khulaifi. _ I spell that for you？（2006 北京

15、） A. Might B. Would C. Can D. Shall,3 Some aspects of a pilots job_ be boring, and pilots often _ work at inconvenient hours. （2006 湖南） A. can；have to B. may；can C. have to; may D. ought to; must,4 The weather turned out to be fine yesterday. I _ the trouble to carry my umbrella with me. (2006 江西） A should have taken B could have taken C neednt have taken D mustnt have taken,5 Hows your tour around the North Lake? I