真实条件句VS非真实条件句

1、真实条件句真实条件句VSVS非真实条件句非真实条件句2017-8-21条件句概述条件句概述12真实条件句真实条件句3非真实条件句非真实条件句4习题巩固习题巩固CONTENTS目目录条件句条件句条件句是指一种表示假设的主从复合句，一般由连词条件句是指一种表示假设的主从复合句，一般由连词 if if 引导引导的条件从句引出某种假设，再由主句表示基于这种假设下的反的条件从句引出某种假设，再由主句表示基于这种假设下的反馈馈。常译为常译为“如果或假如如果或假如那么那么”。分为真实条件句和非真实条件句，前者使用陈述语气，后者需分为真实条件句和非真实条件句，前者使用陈述语气，后者需用虚拟语气。条件句主句和从

2、句的动词需遵守时态一致律。用虚拟语气。条件句主句和从句的动词需遵守时态一致律。表示现实中可能实现的情况。表示现实中可能实现的情况。在真实条件句中，从句的谓语动词一般用在真实条件句中，从句的谓语动词一般用一般现在时来代一般现在时来代替一般将来时；用一般过去时来代替过去将来时替一般将来时；用一般过去时来代替过去将来时。 1. If it _ (rain)tomorrow, I will stay at home. 2. They said they would let us know if they _ any news about him. 真实条件句真实条件句rainsheard 如果主句用的

3、是一般将来时，如果主句用的是一般将来时，if if 引导的条件状引导的条件状 语从句常用一般现在时。语从句常用一般现在时。 如果主句是祈使句，从句用如果主句是祈使句，从句用_。 如果主句含有情态动词，从句用如果主句含有情态动词，从句用_。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一般现在时一般现在时一般现在时一般现在时时态时态ifif引导的条件状语从句可以

4、放在主句前面，常用逗号隔开；引导的条件状语从句可以放在主句前面，常用逗号隔开；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.语序语序“祈使句祈使句+and (or)+and (or)+陈述句陈述句”在意义上相当于一个含有条在意义上相当于一个含有条件状语从句的复合句。件状语从句的复合句。 Hurry up, or youll be late.= If you dont hurry up, youll be late.“if+“if+否定句否定句”相当

5、于相当于“unless+“unless+肯定句肯定句”。 Dont come in if I dont call you. = Dont come in unless I call you.转换转换也叫虚拟条件句，表示与现实情况相反的假设情况。也叫虚拟条件句，表示与现实情况相反的假设情况。主句和从句中的谓语动词都需要使用主句和从句中的谓语动词都需要使用虚拟语气虚拟语气。在表示与事实相反的虚拟语气时，谓语动词有三种形式。在表示与事实相反的虚拟语气时，谓语动词有三种形式。非真实条件句非真实条件句1. 1. 与现在事实相反与现在事实相反if if 条件句：条件句：_主句主句：_一般过去式（was用w

6、ere）would/should/could/might+动词原形1. If I _(come) into a fortune, I _(give) up e into a fortune( (继承一笔遗产，发财）继承一笔遗产，发财）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. 与过去事实相反与过去事实相反if if 条件句：条件句：_主句

7、主句：_过去完成时 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. 与将来事实相反与将来事实

8、相反if if 条件句：条件句：_主句主句：_一般过去式/ were to do/ should dowould/should/could/might+动词原形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?如果他要是来了，我们该和他说些什么呢were to misswouldt get were

9、 to arriveshould have were to comeshould we say所述情况所述情况条件状语从句条件状语从句主句主句与现在事实相反与现在事实相反与过去事实相反与过去事实相反与将来事实相反与将来事实相反注意：上述注意：上述主句的谓语主句的谓语中，中，wouldwould表示结果，表示结果，mightmight表示可表示可能性，能性，couldcould表示能力、允许或可能性，表示能力、允许或可能性，shouldshould表应该，主表应该，主要用于第一人称后。要用于第一人称后。1. 1. 虚拟语气用于条件状语从句中，主句和从句谓语动词的形式虚拟语气用于条件状语从句中，主

10、句和从句谓语动词的形式过去一般时（过去一般时（bebe用用werewere）would/should/could/ might+ +动词原形动词原形had+had+过去分词过去分词would/should/could/ might+have+ +过去分词过去分词动词的过去式动词的过去式 were to+ +动词原形动词原形 should+ +动词原形动词原形would/should/could/ might+ +动词原形动词原形2. 2. 错综时间虚拟条件句错综时间虚拟条件句当条件状语从句表示的行为和主句表示的行为当条件状语从句表示的行为和主句表示的行为所发生的时间不一所发生的时间不一致致时，

11、被称为时，被称为“错综时间条件句错综时间条件句”，动词的形式要根据它所表示，动词的形式要根据它所表示的时间作相应调整。的时间作相应调整。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的虚拟条件从句的用法的虚拟条件从句的用法在非真实条件句中，如果条件从句的谓语中含有在非真实条件句中，如果条件从句的谓语中含有were,hadwe

12、re,had或或shouldshould，可，可将将ifif省略，而把这几个词放在句首，构成倒装，其意义与带省略，而把这几个词放在句首，构成倒装，其意义与带ifif的条件从的条件从句相同句相同。1. If I were you, I would learn to ski._here earlier, you _ her.如果你到的早点的话，你就见到她了。如果你到的早点的话，你就见到她了。_tomorrow, the picnic would be put off.万一明天下雨的话万一明天下雨的话Had you arrivedwould have seenWere I you,Should it

13、 rain4. 4. 含蓄条件句含蓄条件句在上下文情况清楚的情况下，条件从句或主句有时可省略，条件从句在上下文情况清楚的情况下，条件从句或主句有时可省略，条件从句不表达出来，只暗含在上下文中。条件句的意思通常用不表达出来，只暗含在上下文中。条件句的意思通常用without，otherwise(否则），否则），or， but for，were it not for等方式表达。等方式表达。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（犹豫）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(远程通讯), 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