真實(shí)條件句和非真實(shí)條件句

1、真實(shí)條件句和非真實(shí)條件句(虛擬語氣)英語中的條件句分為真實(shí)條件句和非真實(shí)條件句。一、真實(shí)條件句：表示現(xiàn)實(shí)情況中可能實(shí)現(xiàn)的情況。真實(shí)條件句中的謂語動詞一 般用一般現(xiàn)在時代替一般將來時，用一般過去式代替過去將來時。例如：If it rains tomorrow, I will stay at home.They said they would let us know if they heard any news about him.【詳解】條件狀語從句表示主句動作發(fā)生的條件，通常由if來引導(dǎo)，作“如果那么講。詳解例句時態(tài) 如果主句用的是一般將來 時，if引導(dǎo)的條件狀語從句常用一般 現(xiàn)在時。 如果主

2、句是祈使句，從句 也常用一般現(xiàn)在時。 如果主句含有情態(tài)動詞，從句一般也用一般現(xiàn)在時。I will visit my gran dmother if I am free.Let s go shopping if you are not busy.You must be careful if you go swimming in the river.語序if引導(dǎo)的條件狀語從句可以 放在主句前面，常用逗號隔開；也可 以放在主句的后面。If you don t hurry, you will be late.=You will be late if you don t hurry.轉(zhuǎn)換 “祈使句+an

3、d (or)+陳述句在意義上相當(dāng)于一個含有條件狀 語從句的復(fù)合句。 “ if+否認(rèn)句相當(dāng)于uni ess+肯疋句 。Hurry up, or you ll be late. =If you don t hurry up, you ll be late.Don t comein if 1 don t call you.=Don t comei n uni ess I call you.注：當(dāng)連詞if作“是否講時，if引導(dǎo)的從句的時態(tài)要根據(jù)具體情況而定【中考鏈接】()1. I hear Jack Chan will come to Laiwu next week.(2021 山東萊蕪)Really

4、he comes, my youn ger sister will be very happy.A. If B. U ntilC. U nl ess D. Before( ) 2. I don t know if it tomorrow. If it , we won t goon a picnic.(2021 四川內(nèi)江) A. rains; rains B. will rain; rainsC. will rain; will rain( ) 3. Wewill have no water to drink we dont protect the earth.( 2021上海)A. unti

5、lB. beforeC. thoughD. if【穩(wěn)固練習(xí)】I. 單項(xiàng)選擇( ) 1. We will stay at home if my aunt to visit us tomorrow.A. comeB. comesC. will come D. is coming( ) 2. Do you know if he to play basketball with us I think he will come if he free tomorrow.A. comes; is B. comes; will beC. will come; isD. will come; will be( )

6、 3. You will keep healthy you do more exercise, such as runningand swimming.A. ifB. howC. beforeD. wheren .根據(jù)漢語意思完成以下句子，每空一詞。4. 如果明天不下雨的話，我們將去動物園。We will go to the zoo tomorrow.5. 如果你完成了作業(yè)，我們就去下象棋。 , let s go to play chess.6. 如果人人都能保護(hù)環(huán)境，世界將會變得更美好。If everyone protects the environment, the world Key：二

7、、非真實(shí)條件句 : 也叫虛擬條件句， 表示與現(xiàn)實(shí)情況相反的假設(shè)情況。 主句和 從句中的謂語動詞都需要使用虛擬語氣。 在表示與事實(shí)相反的虛擬語氣時， 謂語 動詞有三種形式。其具體形式如下：時間概念條件從句中的謂語動詞主句中的謂語動詞與現(xiàn)在事實(shí)相反 did/were would(could/should/ might)+do 與過去事實(shí)相反 had done/been would(could/should/might)+have done與將來事實(shí)相反 did/werewould(could/should/ might)+ doshould do were to do注意：1.上述主句的謂語中，w

8、ould表示結(jié)果，might表示可能性，could表示 能力、允許或可能性，should主要用于第一人稱后。2. 條件從句的謂語動詞為be時，不管其主語是單數(shù)還是復(fù)數(shù)通常用were。例如：If he were here now, we could ask him about it.(與現(xiàn)在事實(shí)相反)3混合條件句。當(dāng)條件狀語從句表示的行為與主句表示的行為所發(fā)生的時間不 一致時，動詞的形式要根據(jù)它所表示的時間做出相應(yīng)的調(diào)整。例如：If he had followed the doctor s advice then, he would be quite all right now.(從句表示過去時

9、間，主句表示現(xiàn)在時間)4. (省if )倒裝的虛擬條件句。 虛擬條件句的從句局部如果含有 were, should 或had,可將if省略，把were, should或had移到從句主語前形成倒裝。例如： Had I seen him the n, I would have bee n very happy.5. If it weren t for和If it hadn t been for 是兩個很常用的虛擬語氣句型，其意為“假設(shè)不是(有)，要不是有。前者談?wù)摤F(xiàn)在的情況，后者談?wù)?過去的情況?！炯磳W(xué)即練】一、用動詞的適當(dāng)形式填空。1. What will you do if it(rai n

10、) tomorrowWe have to carry it on, since we ve got everything ready.2. She told me that she would not go with me if it(rai n) then ext day.3. If I(be) you, I would pla nt some trees round the house.4. If I had bee n you the n, I(not quarrel) with him.5. If the Un ited States had built more homes for

11、poor people in 1955，the housing problems now in someparts of this country (not be)so serious.二、選擇填空1. Joh n went to the hospital alone.If heme about it, I would have gone with him.A. should tell B. tellsC. told D. had told2. If wethe other road, we might have arrived here in time forthe meeti ng.A.

12、take B. had take nC. took D. have take n3. If hemy advice, he wouldn t have lost his job.A. followed B. should followC. had followed D. would follow4. Had I known about this computer program, a huge amount of time and energyA. would have bee n savedB. had bee n savedC. will be savedD. was saved5. fo

13、r the free tickets, I would not have gone to the films soofte n.A. If it is not B. Were it notC. Had it not been D. If they were not6. The weather has bee n very hot and dry.Yes. If it had rained even a drop, things would be much better now! And my vegetables.A. wouldn t die B. didn t dieC. hadn t d

14、ied D. wouldn t have died補(bǔ)充：狀語從句(Adverbial Clauses )指用作狀語起副詞作用的句子。根據(jù)其 作用可分為時間、原因、條件、目的、結(jié)果、讓步、方式和比擬等從句。英語中常見狀語從句的分類及常用的引導(dǎo)詞：類型常用的引導(dǎo)詞時間狀語從句when, as, while, after, before, till (until),as soon as,since原因狀語從句because, sin ce, as結(jié)果狀語從句so that, such that目的狀語從句so that, i n order that條件狀語從句if, uni ess, as lon

15、g as讓步狀語從句although, though, even if (though)【例句觀察】When I came into the room, my brother was play ing on the computer.我進(jìn)到屋里的時候，弟弟在玩電腦。Since you are in China, you must obey the Chinese law.因?yàn)槟阍谥袊?，所以你必須要遵守中國的法律。The old man was so excited that he could not say a word.老人沖動得一句話也說不出來了。Speak clearly, so tha

16、t they may un dersta nd you.請你說清楚點(diǎn)，以便大家都能明白。You may borrow the book as long as you keep it clea n.只要你保持這本書清潔，你就可以借。He went out even if it was raining hard.盡管雨下得很大，他還是出去了?！緶剀疤崾尽吭跁r間和條件狀語從句中，主句是一般將來時，從句通常用一般現(xiàn)在時表示 將來。如：Jenny will go with them if she is in vited.如果被邀請，詹妮就會和他們一起去。原因和讓步狀語從句的連詞在漢語翻譯中經(jīng)常是成對出現(xiàn)

17、的，即“因?yàn)?所以、“雖然但是，而在英語中，這種關(guān)聯(lián)詞不可成對出現(xiàn)， 只能用其一。I didn t catch the bus because I got up late.因?yàn)槲移鹜砹?，所以沒趕上公車?！痉€(wěn)固練習(xí)】()1. Tomorrow is Father s Day. What will you do for your fatherI will say “I love you, Dad as soon as he up.A. will sta nd B. is waki ng C. wakesD. sta nd()2. My brother will work in another factory the companyoffers him more mon ey.A. after B. whe nC. uni essD. besides()3. The old man always enjoys swimmi ngit is cold.A. soB. butC. because D. though()4. Why were you late for school this morning I missed the first bus.A. Because B. When C. IfD. As( ) 5. I was hap