1、Unit 3 Understanding each other,Grammar and usage Unreal conditionals 虛擬語(yǔ)氣中的非真實(shí)條件句,虛擬語(yǔ)氣可用于條件句和其它一些從句中。虛擬語(yǔ)氣用于條件句中比較多，情況也比較復(fù)雜，所以要特別加以注意。首先要判斷一下是否應(yīng)該用虛擬語(yǔ)氣，因?yàn)闂l件句分為兩種，一種是真實(shí)條件句，一種是非真實(shí)條件句，只有在非真實(shí)條件句中才用虛擬語(yǔ)氣，在真實(shí)條件句中，要用陳述語(yǔ)氣。,虛擬語(yǔ)氣的介紹,Observe the following sentences and tell whether they are real or unreal condit

2、ional clauses.,If we go on polluting the world, it wont be fit for us to live in. If you are busy doing your homework, I wont interrupt you. If you have finished cleaning the classroom, you can go home now. (Under these conditions, the things are sure to happen.),If there were a lot of good restaura

3、nts in the city, this would make it more attractive. (There arent many good restaurant now.) If a lot of people spoke English, it would be very helpful for tourists. (Not many people can speak English now.),非真實(shí)條件句的時(shí)態(tài)表達(dá),如果假設(shè)的情況完全不存在或者實(shí)現(xiàn)的可能性很小,可以說(shuō)幾乎沒(méi)有時(shí),就需要用虛擬語(yǔ)氣來(lái)表達(dá),也就是說(shuō),這時(shí)的條件句是非真實(shí)的條件句。此時(shí)的句子時(shí)態(tài)比真實(shí)條件句中的時(shí)態(tài)

4、后退一步。,虛擬語(yǔ)氣,一、條件從句和主句中的虛擬語(yǔ)氣,主語(yǔ) +should/would/could/might +動(dòng)詞原形,主語(yǔ)+should/would/could/might + have+過(guò)去分詞,注意： 在if I /he/she/it 之后，可用were代替was。兩者在意義上沒(méi)有區(qū)別，但是were更為正式，特別是在陳述心存懷疑的事情時(shí)，如： If she were ready, we would go.,在與將來(lái)事實(shí)相反的條件從句中，我們可以用were to或should +do來(lái)表示,如: If I were to fail my English test, I would ha

5、ve to take it again at the end of the term. If he should come tomorrow, I would talk to him about it.,在非真實(shí)條件句中，如果有were，had，should，我們可以將if省略，把這些詞置于句首，采用倒裝形式，如: If I should meet her, I would tell her. = Should I meet her, I would tell her.,虛擬條件句中的省略與倒裝,If I were in your position, I would do it better.

6、 = Were I in your position, I would do it better. If they had made preparations, they would have succeeded. =Had they made preparations, they would have succeeded.,有時(shí)非真實(shí)條件句中，主句謂語(yǔ)動(dòng)詞所表示的動(dòng)作和條件從句中謂語(yǔ)動(dòng)詞所表示的動(dòng)作并不同時(shí)發(fā)生，這時(shí)動(dòng)詞的形式并不完全按照上述表格來(lái)進(jìn)行，而需要按照各自的時(shí)間來(lái)調(diào)整，這樣的句子就叫錯(cuò)綜時(shí)間條件句。,錯(cuò)綜時(shí)間條件句,e.g. If you had followed the doc

7、tors advice, then you would be all right now. If I hadnt finished my composition by now, I would be working on it tomorrow. If she had prepared well for her lessons yesterday, she wouldnt have so many difficulties now.,有時(shí)一個(gè)假設(shè)的情況并不用條件從句表示,而用其它方式來(lái)表示,這樣的句子叫含蓄條件句。,用with，without, under , but for等介詞短語(yǔ)或分詞短

8、語(yǔ)或者獨(dú)立主格結(jié)構(gòu)來(lái)代替條件從句。,二、 含蓄條件句,e.g. We might have died without your help. =We might have died if you hadnt helped us. Having known in time, we could have stopped it. = If we had known in time, we could stopped it.,We could have done better under more favorable conditions (= if we had been given more fav

9、orable conditions). Without your help (= If you hadnt helped me), I couldnt have succeeded. But for the heavy traffic (= If the traffic had not been so heavy), we would have arrived earlier. He would have given you more help, but he has been so busy (= if he had not been so busy).,在條件從句中除最常見(jiàn)的連詞之外,尚有

10、下列連詞: otherwise; in case; but that; on condition that; unless; suppose/supposing (that); so long as; provided/providing (that),2. 用相當(dāng)于if 的其他連詞表示虛擬結(jié)構(gòu),e.g. I was busy last week, otherwise I would have come to see you. But that you had offered help, they couldnt have finished their work on time.,三、虛擬語(yǔ)氣

11、的常用句型,1、動(dòng)詞wish后的賓語(yǔ)從句中， had done /(could /would have done) wish did /were would / could / might do How I wish I was there with you. I wish I hadnt lost the chance. I wish he would / could / might go with us to the theatre.,sb. + had done 2. If only sb. + did / were sb. + would / could do 要是我能在一天里把英語(yǔ)學(xué)

12、好就好了。 要是我聽了他的建議就好了。 要是Simon能給我回信就好了 。,3、 would sooner would rather I would sooner he left on the earlier train. Id rather you went tomorrow. Id rather you hadnt done that.,（that ）主語(yǔ)+ had done (過(guò)去),(that) 主語(yǔ)+ did / were ( 現(xiàn)在，將來(lái)),She is walking slowly as if she were tired. She talked about the film as

13、 if he had seen it.,主語(yǔ) + had done 4. as if /as though 主語(yǔ) + did /were 主語(yǔ)+ would / could / might do,但as if / as though 后的從句也常用陳述句與其，往往是可能發(fā)生的或真實(shí)的。,It looks as if we are going to win .,主語(yǔ)+ would have done (過(guò)去) 5. If it were not for ， 如果沒(méi)有 if it had not been for 主語(yǔ)+ should / would do （現(xiàn)在）,If it were not

14、for the rain , the crops would die. If it had not been for your timely help , I would have failed.,6.在狀語(yǔ)從句引導(dǎo)詞后 在由lest, for fear that, in case等引導(dǎo)的從句中，虛擬語(yǔ)氣的形式為“should +動(dòng)詞原形”。如： I ran as fast as possible lest I should be too late. I was afraid to open the door lest he should follow me. He ran away for

15、fear that he should be caught.,在由in order that, so that或that引導(dǎo)的目的狀語(yǔ)從句中，虛擬語(yǔ)氣的形式為“may / might / could +動(dòng)詞原形”。如： In order that everybody may understand it, write it in simple language. I gave him the book so that he might read it on the train.,四、固定句式中的運(yùn)用 1.表示“建議、命令、要求、堅(jiān)決做”等動(dòng)詞（如demand, suggest, advise,

16、propose, insist, order, request, desire, urge, deserve, recommend, intend等）后的賓語(yǔ)從句中謂語(yǔ)常用“（should +）動(dòng)詞原形”。如：,I suggest you (should) have enough sleep. I recommend that everyone (should) attend the party. Our only request is that this (should) be settled as soon as possible. He made the decision that no

17、thing (should) hold him back., It + be + suggested / demanded + that 引導(dǎo)的主語(yǔ)從句 suggestion, proposal 引導(dǎo)的同位語(yǔ)從句 It is+ important / necessary + that 從句 Its high (about) time + sb. did sth. should do sth Should 不能省略,如：I would have given you more money, but I was poor then. I would have called you, but I fo

18、rgot your telephone number.,五. 通過(guò)上下文來(lái)虛擬,_ for the free tickets, I would not have gone to the films so often. A. If it is not B. Were it not C. Had it not been D. If they were not,Practice,2. He came late, otherwise he _ the first bus. A. caught B. would catch C. would have caught D. had caught 3. Ma

19、ry was going to the wedding if her friend _ her. A. hadnt called on B. didnt call at C. didnt call on D. hadnt called at,4. -Lets stop watching the boring TV programme, Jack! -If you dont watch it, I _ , either. A. dont B. wont C. am not D. stop,5.-Shall I tell John about the bad news? -No, you _. I

20、 think that will make him sad. A. neednt B. wouldnt C. shouldnt D. mustnt,6. Why did you throw the bottle out of the window? You _ somebody. A. might hurt B. could have hurt C. would hurt D. must have hurt 7.-Mum, may I got out and play? -No, you _ . A. wont B. dont C. arent able to D. cant,8. From

21、what I hear about their hotel and the weather, they _ their holiday very much. A. would have enjoyed B. shouldnt have enjoyed C. neednt have enjoyed D. cant have enjoyed,9.-Did you hear me come in last night? -No, I _ asleep. A. cant be B. must be C. must have been D. couldnt have been,10.-Ill pay you by cheque monthly. -Id rather you _ me