真实条件句VS非真实条件句.ppt

1、A,1,真实条件句VS非真实条件句,2017-8-21,A,2,条件句概述,1,2,真实条件句,3,非真实条件句,4,习题巩固,CONTENTS,目,录,A,3,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 if 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馈。 常译为“如果或假如那么”。 分为真实条件句和非真实条件句，前者使用陈述语气，后者需用虚拟语气。条件句主句和从句的动词需遵守时态一致律。,A,4,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。 1. If it _ (rain)tomor

2、row, I will stay at home. 2. They said they would let us know if they _ any news about him.,真实条件句,rains,heard,A,5,如果主句用的是一般将来时，if 引导的条件状 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 s

3、wimming in the river.,am,一般现在时,一般现在时,时态,A,6,if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。 If you dont hurry, you will be late. = You will be late if you dont hurry.,语序,A,7,“祈使句+and (or)+陈述句”在意义上相当于一个含有条件状语从句的复合句。 Hurry up, or youll be late. = If you dont hurry up, youll be late. “if+否定句”相当于“unless+肯定句”。 Do

4、nt come in if I dont call you. = Dont come in unless I call you.,转换,A,8,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。,非真实条件句,A,9,1. 与现在事实相反,if 条件句：_ 主句：_,一般过去式（was用were）,would/should/could/might+动词原形,1. If I _(come) into a fortune, I _(give) up working. come into a fortune(

5、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.,came,would give,knew,could tell,left,should arrive,A,10,1. 与过去事实相反,if 条件句：_ 主句：_,过去完成时 had done,would/should/could/might+have done,1. If I _(leave) sooner, I _(catch) the bus. 2. We _(ca

6、ll) you if we _(know) your telephone number. 3. If she _ (take) the medcine, she _ (fell) much better.,had left,would have caught,would have called,had known,had taken,would have felt,A,11,3. 与将来事实相反,if 条件句：_ 主句：_,一般过去式/ were to do/ should do,would/should/could/might+动词原形,1. If we _(miss) the 10 ocl

7、ock 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 miss,wouldt get,were to arrive,should have,were to come,should we say,A,12,注意：上述主句的谓语中，would表示结果，might表示可能性，could表示能力、允许或可能

8、性，should表应该，主要用于第一人称后。,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,过去一般时（be用were）,would/should/could/ might+动词原形,had+过去分词,would/should/could/ might+have+过去分词,动词的过去式 were to+动词原形 should+动词原形,would/should/could/ might+动词原形,A,13,2. 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所发生的时间不一致时，被称为“错综时间条件句”，动词的形式要根据它所表示的时间作相应调整。 1. If the

9、y had worked hard, they would be very tired. 2.If he _(follow) the doctors advice then, he _ (be) quite all right now.,had followed,would be,A,14,3. 省略if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were,had或should，可将if省略，而把这几个词放在句首，构成倒装，其意义与带if的条件从句相同。 1. If I were you, I would learn to ski. _here earlier, you _

10、 her. 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,Had you arrived,would have seen,Were I you,Should it rain,A,15,4. 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），or， but for，were it not for等方式表达。 If it were not for their help, we could not g

11、et over the difficulities. But for their help, Without their help， Im ill; otherwise I would visit my grandpa.,A,16,1. 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 ti

12、me. A. can not finish B. will not finish C. had not finisd D. could not 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. get,D,D,B,A,17,4. If it _for his teachers help, my brother wouldnt have passed the Engli

13、sh exam so easily last term. A. werent B. hadnt been C. hasnt been D.wouldnt be 5. If you _in the exam, you will let him down. A. fail B. will fail C. failed D. would fail 6. 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 go,B,A,A,A,

14、18,7. If you _late, you would have caught the first bus. A. wont be B. havent been C. arent D.hadnt been 8. I would have gone to the meeting if I _time A. had B. have had C. had had D. would have had 9. I didnt see your sister at the meeting. If she _, I would have met her. A. has come B. did come C

15、. came D. had come,D,C,D,A,19,1. If everyone _(protect) the environment, the world will become better. 1. We _(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 be,were,have won,had taken,protects,A,20,1. If you listened to the doctor, you would be