真實條件句VS非真實條件句

1、真實條件句真實條件句VSVS非真實條件句非真實條件句2017-8-21條件句概述條件句概述12真實條件句真實條件句3非真實條件句非真實條件句4習題鞏固習題鞏固CONTENTS目目錄條件句條件句條件句是指一種表示假設的主從復合句，一般由連詞條件句是指一種表示假設的主從復合句，一般由連詞 if if 引導引導的條件從句引出某種假設，再由主句表示基于這種假設下的反的條件從句引出某種假設，再由主句表示基于這種假設下的反饋饋。常譯為常譯為“如果或假如如果或假如那么那么”。分為真實條件句和非真實條件句，前者使用陳述語氣，后者需分為真實條件句和非真實條件句，前者使用陳述語氣，后者需用虛擬語氣。條件句主句和從

2、句的動詞需遵守時態(tài)一致律。用虛擬語氣。條件句主句和從句的動詞需遵守時態(tài)一致律。表示現實中可能實現的情況。表示現實中可能實現的情況。在真實條件句中，從句的謂語動詞一般用在真實條件句中，從句的謂語動詞一般用一般現在時來代一般現在時來代替一般將來時；用一般過去時來代替過去將來時替一般將來時；用一般過去時來代替過去將來時。 1. If it _ (rain)tomorrow, I will stay at home. 2. They said they would let us know if they _ any news about him. 真實條件句真實條件句rainsheard 如果主句用的

3、是一般將來時，如果主句用的是一般將來時，if if 引導的條件狀引導的條件狀 語從句常用一般現在時。語從句常用一般現在時。 如果主句是祈使句，從句用如果主句是祈使句，從句用_。 如果主句含有情態(tài)動詞，從句用如果主句含有情態(tài)動詞，從句用_。1. I will visit my grandmother if I _ free. 2. Lets go shopping if you are not busy. 3. You must be careful if you go swimming in the river.am一般現在時一般現在時一般現在時一般現在時時態(tài)時態(tài)ifif引導的條件狀語從句可以

4、放在主句前面，常用逗號隔開；引導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。也可以放在主句的后面。 If you dont hurry, you will be late. = You will be late if you dont hurry.語序語序“祈使句祈使句+and (or)+and (or)+陳述句陳述句”在意義上相當于一個含有條在意義上相當于一個含有條件狀語從句的復合句。件狀語從句的復合句。 Hurry up, or youll be late.= If you dont hurry up, youll be late.“if+“if+否定句否定句”相當

5、于相當于“unless+“unless+肯定句肯定句”。 Dont come in if I dont call you. = Dont come in unless I call you.轉換轉換也叫虛擬條件句，表示與現實情況相反的假設情況。也叫虛擬條件句，表示與現實情況相反的假設情況。主句和從句中的謂語動詞都需要使用主句和從句中的謂語動詞都需要使用虛擬語氣虛擬語氣。在表示與事實相反的虛擬語氣時，謂語動詞有三種形式。在表示與事實相反的虛擬語氣時，謂語動詞有三種形式。非真實條件句非真實條件句1. 1. 與現在事實相反與現在事實相反if if 條件句：條件句：_主句主句：_一般過去式（was用w

6、ere）would/should/could/might+動詞原形1. If I _(come) into a fortune, I _(give) up e into a fortune( (繼承一筆遺產，發(fā)財）繼承一筆遺產，發(fā)財）2. If I _(know) how it works, I _(tell) you what to do.3. If we _ (leave) now, we _ (arrive) in time.camewould giveknewcould tellleftshould arrive1. 1. 與過去事實相反與過去事實相反if if 條件句：條件句：_主句

7、主句：_過去完成時 had donewould/should/could/might+have done1. If I _(leave) sooner, I _(catch) the bus.2. We _(call) you if we _(know) your telephone number.3. If she _ (take) the medcine, she _ (fell) much better.had leftwould have caughtwould have calledhad knownhad takenwould have felt3. 3. 與將來事實相反與將來事實

8、相反if if 條件句：條件句：_主句主句：_一般過去式/ were to do/ should dowould/should/could/might+動詞原形1. If we _(miss) the 10 oclock train, we _(get) there till after lunch.2. If our train_(arrive) on time, we _(have) time to visit your sister. 3. If he _(come), what _ to him?如果他要是來了，我們該和他說些什么呢were to misswouldt get were

9、 to arriveshould have were to comeshould we say所述情況所述情況條件狀語從句條件狀語從句主句主句與現在事實相反與現在事實相反與過去事實相反與過去事實相反與將來事實相反與將來事實相反注意：上述注意：上述主句的謂語主句的謂語中，中，wouldwould表示結果，表示結果，mightmight表示可表示可能性，能性，couldcould表示能力、允許或可能性，表示能力、允許或可能性，shouldshould表應該，主表應該，主要用于第一人稱后。要用于第一人稱后。1. 1. 虛擬語氣用于條件狀語從句中，主句和從句謂語動詞的形式虛擬語氣用于條件狀語從句中，主

10、句和從句謂語動詞的形式過去一般時（過去一般時（bebe用用werewere）would/should/could/ might+ +動詞原形動詞原形had+had+過去分詞過去分詞would/should/could/ might+have+ +過去分詞過去分詞動詞的過去式動詞的過去式 were to+ +動詞原形動詞原形 should+ +動詞原形動詞原形would/should/could/ might+ +動詞原形動詞原形2. 2. 錯綜時間虛擬條件句錯綜時間虛擬條件句當條件狀語從句表示的行為和主句表示的行為當條件狀語從句表示的行為和主句表示的行為所發(fā)生的時間不一所發(fā)生的時間不一致致時，

11、被稱為時，被稱為“錯綜時間條件句錯綜時間條件句”，動詞的形式要根據它所表示，動詞的形式要根據它所表示的時間作相應調整。的時間作相應調整。1. If they had worked hard, they would be very tired.2.If he _(follow) the doctors advice then, he _ (be) quite all right now.had followedwould be3. 3. 省略省略ifif的虛擬條件從句的用法的虛擬條件從句的用法在非真實條件句中，如果條件從句的謂語中含有在非真實條件句中，如果條件從句的謂語中含有were,hadwe

12、re,had或或shouldshould，可，可將將ifif省略，而把這幾個詞放在句首，構成倒裝，其意義與帶省略，而把這幾個詞放在句首，構成倒裝，其意義與帶ifif的條件從的條件從句相同句相同。1. If I were you, I would learn to ski._here earlier, you _ her.如果你到的早點的話，你就見到她了。如果你到的早點的話，你就見到她了。_tomorrow, the picnic would be put off.萬一明天下雨的話萬一明天下雨的話Had you arrivedwould have seenWere I you,Should it

13、 rain4. 4. 含蓄條件句含蓄條件句在上下文情況清楚的情況下，條件從句或主句有時可省略，條件從句在上下文情況清楚的情況下，條件從句或主句有時可省略，條件從句不表達出來，只暗含在上下文中。條件句的意思通常用不表達出來，只暗含在上下文中。條件句的意思通常用without，otherwise(否則），否則），or， but for，were it not for等方式表達。等方式表達。If it were not for their help, we could not get over the difficulities.But for their help, Without their h

14、elp， Im ill; otherwise I would visit my grandpa.1. He hesitated（猶豫）for a moment before kicking the ball, otherwise he _a goal.A. had scored B. scored C. would scored D.would have scored.2. But for their help, we _the program in time.A. can not finish B. will not finish C. had not finisd D. could not

15、 have finished.3. They _ two free tickets to Canada, otherwise theyd never have been able to afford to go.A. had got B. got C. have got D. getDDB4. If it _for his teachers help, my brother wouldnt have passed the English exam so easily last term.A. werent B. hadnt been C. hasnt been D.wouldnt be5. I

16、f you _in the exam, you will let him down.A. fail B. will fail C. failed D. would fail6. If I were to have time, I _to the theatre tomorrow evening.A. should go B.would have gone C. had gone D. were to goBAA7. If you _late, you would have caught the first bus. A. wont be B. havent been C. arent D.ha

17、dnt been8. I would have gone to the meeting if I _timeA. had B. have had C. had had D. would have had9. I didnt see your sister at the meeting. If she _, I would have met her.A. has come B. did come C. came D. had comeDCD1. If everyone _(protect) the environment, the world will become better.1. We _

18、(be) back in the hotel now if you didnt lose the map.2. If there _(be) no modern telecommunications(遠程通訊), we would have to wait for weeks to get news from around the world.3. But for the help of my English teacher, I wouldnt _(win)the first prize in the English Writing Competition.4. If we _(take) the other road, we might have not missed the train.would bewerehave wonhad takenprote