高中英語(yǔ)必修3第一單元語(yǔ)法

1、Unit 1Discovering useful structures - Modal Verbs (I)情態(tài)動(dòng)詞的語(yǔ)法特征情態(tài)動(dòng)詞的語(yǔ)法特征 情態(tài)動(dòng)詞有一定的意義，表示或暗示某種情緒或情態(tài)動(dòng)詞有一定的意義，表示或暗示某種情緒或 態(tài)度，表示可能、建議、愿望、必要、允許、態(tài)度，表示可能、建議、愿望、必要、允許、能力等。能力等。 2. 情態(tài)動(dòng)詞沒(méi)有人稱和數(shù)的變化，即不隨主語(yǔ)的不情態(tài)動(dòng)詞沒(méi)有人稱和數(shù)的變化，即不隨主語(yǔ)的不同而變化。同而變化。 3. 情態(tài)動(dòng)詞不能獨(dú)立使用，必須和實(shí)義動(dòng)詞一起構(gòu)情態(tài)動(dòng)詞不能獨(dú)立使用，必須和實(shí)義動(dòng)詞一起構(gòu)成謂語(yǔ)。成謂語(yǔ)。4. 情態(tài)動(dòng)詞除情態(tài)動(dòng)詞除ought和和have外，后

2、面只能接不帶外，后面只能接不帶to的的 不定式。不定式。5. 情態(tài)動(dòng)詞沒(méi)有非謂語(yǔ)形式，即沒(méi)有不定式、分詞情態(tài)動(dòng)詞沒(méi)有非謂語(yǔ)形式，即沒(méi)有不定式、分詞等形式。等形式。 must 表示必須，表示必須， 多處于義務(wù)、責(zé)任或強(qiáng)制命令多處于義務(wù)、責(zé)任或強(qiáng)制命令(must提問(wèn)，否定回答用提問(wèn)，否定回答用neednt或或dont have to). You must hand in your homework today. (2) mustnt 表示禁止。意思是表示禁止。意思是“不許不許”、“不準(zhǔn)不準(zhǔn)”、“不可以不可以”。 You mustnt smoke here.(3) 用于發(fā)生了某種于說(shuō)話人的愿望相反、

3、不用于發(fā)生了某種于說(shuō)話人的愿望相反、不受歡迎的事時(shí)，意思是受歡迎的事時(shí)，意思是“偏偏偏偏”、“偏要偏要”。Why must he do it that way?Why must it rain on Sunday?(4) 表示推測(cè)，表示推測(cè)， 只能用于肯定句。只能用于肯定句。He must be reading novels now.The road is wet. It must have rained lastnight.can /could(1)表示能力表示能力Can you speak Japanese?(2)表示推測(cè)時(shí)，只用在否定句或疑問(wèn)句中。表示推測(cè)時(shí)，只用在否定句或疑問(wèn)句中。He

4、 cant be at home now.(3) 表示允許表示允許(許可或請(qǐng)求許可）許可或請(qǐng)求許可）You can go now, but he cant.(4) 表驚異、懷疑等表驚異、懷疑等How can you be so rude?could可表示能力或可能性，多用于過(guò)去，也可可表示能力或可能性，多用于過(guò)去，也可指現(xiàn)在，通常表示虛擬或作為指現(xiàn)在，通常表示虛擬或作為can的委婉形式。的委婉形式。can / could + have done在肯定句中表示在肯定句中表示“本來(lái)本來(lái)可以做而實(shí)際上沒(méi)做某事可以做而實(shí)際上沒(méi)做某事” ” ；在疑問(wèn)句或否定；在疑問(wèn)句或否定句中表示對(duì)過(guò)去行為的懷疑或不肯

5、定句中表示對(duì)過(guò)去行為的懷疑或不肯定, 表示推表示推測(cè)。測(cè)。 You could have done better, but you didnt try your best. 你本來(lái)可以做得更好，但你沒(méi)努力。你本來(lái)可以做得更好，但你沒(méi)努力。 He cant have been to that town. 他不可能去過(guò)那個(gè)城。他不可能去過(guò)那個(gè)城。may/might(1)表示可能性，表示可能性，might比比may可能性更小?？赡苄愿?。It may be true.He might not come today.(2) 表示請(qǐng)求、許可，多用于肯定和疑問(wèn)句中表示請(qǐng)求、許可，多用于肯定和疑問(wèn)句中May

6、 I ask you a question?(3) 表示愿望表示愿望May you be happy all your life.might 比比 may 語(yǔ)氣更委婉語(yǔ)氣更委婉may/might表示推測(cè)時(shí)，表示對(duì)現(xiàn)在或?qū)?lái)要表示推測(cè)時(shí)，表示對(duì)現(xiàn)在或?qū)?lái)要發(fā)生的事情把握不大。發(fā)生的事情把握不大。might/may have done表示對(duì)表示對(duì)過(guò)去發(fā)生的動(dòng)作過(guò)去發(fā)生的動(dòng)作進(jìn)行的可能性推測(cè)。進(jìn)行的可能性推測(cè)。 He may have gone to the clinic. 他可能去醫(yī)務(wù)室了。他可能去醫(yī)務(wù)室了。 He might have read about the news in the new

7、spaper. 他可能已經(jīng)從報(bào)紙上知道這個(gè)消息了。他可能已經(jīng)從報(bào)紙上知道這個(gè)消息了。will/would 表示意愿，表示意愿，will表示現(xiàn)在的意愿，表示現(xiàn)在的意愿，would表示表示過(guò)去的意愿。過(guò)去的意愿。 Go where you will. She asked if I would go with them.2. 表示征求意見(jiàn)或提出請(qǐng)求，主要用于第二人表示征求意見(jiàn)或提出請(qǐng)求，主要用于第二人稱的疑問(wèn)句中，稱的疑問(wèn)句中，will和和would均可用，均可用，would此時(shí)并不表過(guò)去，而表示委婉語(yǔ)氣。此時(shí)并不表過(guò)去，而表示委婉語(yǔ)氣。 Would Sunday night suit you? W

8、ill / Would you please post the letter for me? 3. 表示習(xí)慣和傾向性表示習(xí)慣和傾向性will表示現(xiàn)在的習(xí)慣，表示現(xiàn)在的習(xí)慣，would表示過(guò)去的習(xí)慣表示過(guò)去的習(xí)慣(=used to do)。 Oil will float on water. When he was a child, he would often go skiing. 4. 表示推測(cè)表示推測(cè)will用于談?wù)摤F(xiàn)在，用于談?wù)摤F(xiàn)在，would可用于談?wù)撨^(guò)去，也可用于談?wù)撨^(guò)去，也可用于談?wù)摤F(xiàn)在可用于談?wù)摤F(xiàn)在( (語(yǔ)氣較委婉語(yǔ)氣較委婉) )。 Ask him. He will know. E

9、very family would have some sort of trouble. I thought you would have finished it by now. shall / should1.在陳述句中在陳述句中,shall用于二、三人稱表示允諾、用于二、三人稱表示允諾、警告、命令、決心等。警告、命令、決心等。 You shall do as I say. (命令命令) Nothing shall stop me doing it. (決心決心) Tell him that he shall have the book tomorrow. (允諾允諾)2. shall在疑問(wèn)

10、句中在疑問(wèn)句中, 用于一、三人稱，用來(lái)表用于一、三人稱，用來(lái)表示請(qǐng)求或征求意見(jiàn)。示請(qǐng)求或征求意見(jiàn)。 Shall I open the window for you？（征求意見(jiàn)）？（征求意見(jiàn)） Shall he fetch some water for you？（請(qǐng)求）？（請(qǐng)求）3. should常表示應(yīng)當(dāng)，意思和常表示應(yīng)當(dāng)，意思和ought to相近，相近，但語(yǔ)氣較弱。但語(yǔ)氣較弱。Young people should learn how to use computers.5. should have done表示責(zé)備或批評(píng)表示責(zé)備或批評(píng),意為意為“本應(yīng)本應(yīng)該該但但” You should h

11、ave told her the truth earlier. She shouldnt have left without saying a word.4. should用于可能性推測(cè)時(shí)用于可能性推測(cè)時(shí), 表表“應(yīng)該，很可能應(yīng)該，很可能” They left at 5:30. They should get there now.1. Jack described his father, who _ a brave boy many years ago, as a strongwilled man. （2010 安徽卷）安徽卷） A. would be B. would have been C

12、. must be D. must have been 答案：答案：D 解析：句意為解析：句意為“杰克把他的父親描述為一杰克把他的父親描述為一個(gè)意志堅(jiān)強(qiáng)的人，他的父親多年前肯定很個(gè)意志堅(jiān)強(qiáng)的人，他的父親多年前肯定很勇敢勇敢”用用must have been表示對(duì)過(guò)去事情表示對(duì)過(guò)去事情的肯定推測(cè)。的肯定推測(cè)。高考真題高考真題2. You _ buy a gift, but you can if you want to. （2010 湖南卷）湖南卷） A. must B. mustnt C. have to D. dont have to 答案：答案：D解析：解析：dont have to 意為意

13、為“沒(méi)有必要沒(méi)有必要”，符合語(yǔ)境，句意為：符合語(yǔ)境，句意為：“你沒(méi)有必要買禮你沒(méi)有必要買禮物，但如果你想買的話，你也可以買。物，但如果你想買的話，你也可以買?！?. I have told you the truth. _ I keep repeating it? （2010 江西卷）江西卷） A. Must B. Can C. May D. Will答案：答案：A解析：解析： must 必須必須, 一定一定 can 可以可以, 能夠，能夠， may 也許，也許，will 意愿意愿, 傾向性動(dòng)作。前半句傾向性動(dòng)作。前半句說(shuō)我告訴你事實(shí)了說(shuō)我告訴你事實(shí)了, 這里用的是現(xiàn)在完成這里用的是現(xiàn)在完成時(shí)

14、時(shí), 表示過(guò)去的動(dòng)作對(duì)現(xiàn)在造成了影響表示過(guò)去的動(dòng)作對(duì)現(xiàn)在造成了影響, 既既然我已經(jīng)說(shuō)了然我已經(jīng)說(shuō)了, 我還必須重復(fù)一遍嗎？我還必須重復(fù)一遍嗎？4. I_ have watched that movie itll give me horrible dreams. （2010山山 東卷）東卷） A. shouldnt B. neednt C. couldnt D. mustnt答案：答案：A解析：句意應(yīng)為解析：句意應(yīng)為“我本來(lái)不應(yīng)該看那部電我本來(lái)不應(yīng)該看那部電影的影的-它會(huì)使我做噩夢(mèng)的。它會(huì)使我做噩夢(mèng)的?！北硎颈硎尽氨颈緛?lái)不應(yīng)該做而做了某事來(lái)不應(yīng)該做而做了某事”用用shouldnt have do

15、ne, 所以所以A項(xiàng)正確。項(xiàng)正確。 As he had heart attack, he was told that he _ continue the work.A. neednt B. may not C. mustnt D. cant 2. An Englishman who _ not speak Italian was once traveling in Italy. A. must B. could C. may D. might 3. I _ like to make a suggestion. A. could B. would C. must D. might 4. I kn

16、ow things are hard with you, but you _ try to get over the difficulties.A. can B. may C. must D. oughtC C B B Choose the best answers.5. We hope that as many people as possible _ join us for the picnic tomorrow. A. may B. must C. should D. can6. I think Ill give Bob a ring. You _. You havent been in

17、 touch with him for ages. A. will B. may C. would D. should 7. Could I have a word with you, Mum? Oh dear, if you _. A. can B. must C. may D. shouldDDB 8. It is usually warm in my hometown in March, but it _ be rather cold sometimes. A. must B. can C. should D. would9. You dont have to know the name

18、 of the author to find a book. You _ find the book by the title. A. must B. need C. can D. would 10. Although this _ sound like a simple task, great care is needed. A. must B. may C. shall D. shouldB C B 11. You _ be hungry already you had lunch only two hours ago! A. wouldnt B. cant C. mustnt D. ne

19、ednt12. According to the air traffic rules, you _ switch off your mobile phone before boarding. A. may B. can C. would D. should13. She _ have left school, for her bike is still here. A. cant B. wouldnt C. shouldnt D. mustntB D A Complete the following sentences using modal verbs. Youve been working all day. You _ be very tired. 2.