If 用法汇总及练习.docx

If 用法汇总及练习If 用法汇总 1、主将从现 ； eg:If it rains(从句) ,I will stay at home. =I will stay at home if it rains. 2、主句含有情态动词 从句为一般现在时； eg:If you drive too fast ,you may have an accident. =You may have an accident if you drive too fast 3、主句为祈使句,从句要用一般现在时态； eg:Don't play computer games if you don't finish your homework. 4、是否=whether Ask if he is at home. I wonder if she is ill. 5、虚拟语气 eg:If I were a bird ,I would fly in the sky. 时态：可以表示过去，现在和将来的情况，它的基本特点是时态退后. a.同现在事实相反的假设 从句用一般过去时 should( would) +动词原形 If they were here,they would help you. b.表示于过去事实相反的假设 从句用过去完成时 should(would) have+ 过去分词 If she had worked harder,she would have succeeded. If my lawyer had been here last Saturday,he would have prevented me from going. c.表示对将来的假想 一般过去时 ， were+ to do， 从句：主+ should/would/could/might+v原形 should+ v原形， If you succeeded,everything would be all right. If you were to succeed,everything would be all right. If you should succeed,everything would be all right. 单项练习 1. If I _ where he lived, I _ a note to him. A. know, would have sent B. had known, would have sent C. know, would send D. knew, would have sent 2. Mary is ill today. If she _, she _ absent from school. A. were not ill; wouldnt be B. had been ill; wouldnt have been C. had been ill; should have been D. hadnt been ill; could be 3. He acted as if he _ everything in the world. A. knew B. knows C. has known D. won't know 4. If you had enough money, what _? A. will you buy B. would you buy C. would you have bought D. will you have bought 5. If Mr. Young _ with justice, he _ such a wrong thing. A. were treated; wouldnt do B. had been treated; wouldnt have done C. were treated; wouldnt have done D. had been treated; wouldnt do 6. What _ if there _ no light during the day? A. will happen; was B. would happen; is C. happens; were D. would happen; were 7. The spokesman acted that way as if he _ anything about the accident but actually he did. A. doesnt hear B. didnt hear C. havent heard D. hadnt heard 8. If it _ not for the fact that you _ ill now, I would surely punish you. A. is; are B. were; were C. were; are D. was; were 9. Many Chinese movie stars now have given up their Chinese nationality. If I were them,I _ that. A. shouldnt do B. didnt do C. hadnt done D. wont do 10. I want to get back by 5 oclock if _. A. likely B. can C. possible D. Probable 11. It seems as if it _ already summer now but it is only February. A. is B. was C. were D. had been 12. If Henry had not pulled his cap low over his brow, he _ by the police. A. might be recognized B. might have been recognized C. would have recognized D. was to have been recognized 13. There is a ring at the door. That _ be the postman, I suppose. A. will B. would C. is going to D. was going to 14. Look at the dark cloudsthere _ be a storm. A. will B. must have been C. is going to D. would 15. Why are you taking the pictures down? I _ the wall. A. paint B. have just painted C. am going to paint D. will have painted 16. Can I stay at home tomorrow? Yes, you can if it_. A. will snow B. is going to snow C. snows D. snowed 17. I dont know if he _ this afternoon. But if he _, I will tell you. A. will come; will do; B. comes; will do C. will come; does D. comes; does 18. I thought I asked you to fix the radio. Oh, Im sorry. I _ it right away. A. am to do B. will do C. was about to do D. am going to do 19. The WTO cant live up to its name _ it does not include a country that is home to one fifth of mankind. A. as long as B. whether C. if D. even though 20. Ask him to ring me up if you _ him. A. see B. saw C. would see D. will see 21. Its so late. I dont think he _ come. A. would B. should C. is going to D. shall 22. If people _ polluting the air, animals and plants will die soon. A. dont stop B. didnt stop C. shall not stop D. havent stopped 23. If you _ an interesting day out, _ the Science Museum. A. want; visiting B. want; visit C. want to; visit D. wanting; visit 24. If the pure water is heated to 100 centigrade degrees, it _ boil. A. is going to B. will C. would D. is to 25. Is a dictionary available, _ so, where? A. if B. if is C. and if D. and if is 15 BAABB 610 DDCAC 1115 CBACC 1620 CCBCA 2125 CABBC 最后一练 1.If you _ to the party, youll have a great time. A. will go B. went C. go D. going 2. It will be a long time _ Peter _ his work. A. since, has finished B. after, finishes C. when, will finish D. before, finishes. 3. What will father _ us from Japan? A. take B. bring C. carry D. make 4. Weifang is famous _ kites. A. for B. to C. on D. with 5 I _ her the answer if she _me. A. can tell, will ask B. will tell, will ask C. would tell, ask D. will tell, asks 6. What are you going to do tomorrow? -Well go to the library tomorrow if it _. A. isnt rain B. rain C. wont rain D. doesnt rain 7.Do you know when he will come back tomorrow? -Sorry, I dont know. When he _ back, Ill tell you. A. comes B. will come C. come D. may come 8. What will you do if you _ to the old folks home visit? A. go B. went C.going D. will go 9. If I eat _ food, Ill be very fat. A. too many B. many too C. too much D. much too 10. Ill give the book to him if he _ here next Sunday. A. will come B. comes C. is coming D. came 11. There _an English film in our school tomorrow. A. is going to have B. will have C. is going to be D. has 12. Could you tell us where _？ A. will the next Olympic Games held B. the next Olympic Games will be held C. would the next Olympic Games be held D. the next Olympic Games would be held 13. When my mother returned last night, I _ a book. A. read B. am reading C. was reading D. am going to read 14.What _ you _ when it began to rain? A. do, do B. were, doing C. are, doing D. did, do 15. Ill wake you up when he _back. A. will B. is going to come C. comes D. come 1-5 CDBAD 6-10 DAACB 11-15 CBCBC