if条件句讲解及练习

if条件句讲解及练习从句主句与现在事实相反过去式（be 用were）would/should/could/might+ do与过去事实相反过去完成式would/should/could/might + have done与将来事实相反should (were to) +动词原形would/should/could/might + doIf I were you, I would not let out the secret. 如果我是你的话，我不会泄露这个秘密的。If I knew his new address, I would tell you.如果我知道他的新地址，我会告诉你的。If he studied harder, he would pass the exam.如果他学习再努力点的话，他会通过考试的。If we had made fuller preparation, we should have won the game. 如果我们做了更充分的准备的话，我们肯定就赢了这场比赛。If you had taken my advice, you wouldnt have been late for the meeting.如果你听了我的建议，你开会就不会迟到了。If she were to/should come, I would tell her the secret.万一她来的话，我会告诉她这个秘密。（2）省略if的虚拟条件句在含有were, had, 或者should 等词的虚拟条件句中，可以省略if, 将were, had或者should这些助动词放在句首。如：Were I you, I would not let out the secret. Had we made fuller preparation, we should have won the game.Had you taken my advice, you wouldnt have been late for the meeting. Should she come, I would tell her the secret.高一语法练习（四）预测、if条件句及虚拟语气一、单项选择1. If I _ where he lived, I _ a note to him.A. know, would have sentB. had known, would have sentC. know, would send D. knew, would have sent2. Mary is ill today. If she _, she _ absent from school.A. were not ill; wouldnt be B. had been ill; wouldnt have beenC. had been ill; should have been D. hadnt been ill; could be3. He acted as if he _ everything in the world.A. knew B. knows C. has known D. wont know4. If you had enough money, what _?A. will you buy B. would you buyC. would you have boughtD. will you have bought5. If Mr. Young _ with justice, he _ such a wrong thing.A. were treated; wouldnt doB. had been treated; wouldnt have doneC. were treated; wouldnt have doneD. had been treated; wouldnt do6. What _ if there _ no light during the day?A. will happen; wasB. would happen; isC. happens; were D. would happen; were7. 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 heard8. 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; were9. 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 do10. I want to get back by 5 oclock if _.A. likely B. can C. possible D. probable11. It seems as if it _ already summer now but it is only February.A. is B. wasC. were D. had been12. If Henry had not pulled his cap low over his brow, he _ by the police.A. might be recognized B. might have been recognizedC. would have recognized D. was to have been recognized13. There is a ring at the door. That _ be the postman, I suppose.A. will B. wouldC. is going toD. was going to14. Look at the dark cloudsthere _ be a storm.A. willB. must have beenC. is going toD. would15. Why are you taking the pictures down?I _ the wall.A. paintB. have just paintedC. am going to paint D. will have painted16. Can I stay at home tomorrow?Yes, you can if it_.A. will snow B. is going to snowC. snows D. snowed17. I dont know if he _ this afternoon. But if he _, I will tell you.A. will come; will do; B. comes; will doC. will come; does D. comes; does18. I thought I asked you to fix the radio.Oh, Im sorry. I _ it right away.A. am to do B. will doC. was about to doD. am going to do19. 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 though20. Ask him to ring me up if you _ him.A. see B. saw C. would see D. will see21. Its so late. I dont think he _ come.A. would B. should C. is going to D. shall22. If people _ polluting the air, animals and plants will die soon.A. dont stop B. didnt stop C. shall not stopD. havent stopped23. If you _ an interesting day out, _ the Science Museum.A. want; visiting B. want; visitC. want to; visit D. wanting; visit24. If the pure water is heated to 100 centigrade degrees, it _ boil.A. is going to B. will C. would D. is to25. Is a dictionary available, _ so, where?A. if B. if is C. and if D. and if is二、翻译句子26. 要是我哥哥在这儿，一切都没问题了。27. 如果下雨，庄稼就得救了。28. 如果你昨天早点来，你就碰见他了。29. 他那样对待我，好像我是他儿子似的。30. 他们谈话的样子好像是多年的朋友一样。31. 我想今天下午不会下雨。32. 你下星期把车借给我行吗？33. 发生的事我谁也不告诉。34. 我们不准备在那里多呆。35. 我难受极了，我想我要生病了。Keys:15 BAABB 610 DDCAC 1115 CBACC 1620 CCBCA2125 CABBC26. If my brother were here, everything would be all right.27. If it should rain, the crops would be saved.28. If you had come earlier yesterday, you would (might) have met him.29. He treats me as if I were his son.30. They are talking as if they had be