if条件句讲解及练习
if条件句讲解及练习
撰稿：胡秋明审稿：赵克险责编：白雪雁
本单元语法讲解
一、 will 和be going to 表示推测、揣想
will 更强调依据直觉、知识和经验做出的推测。例如：
This will be the house you are looking for.
You will be in time if you hurry.
be going to 更强调依据当时可以观察到的证据、事实做出的推测。例如：
Look at those clouds. I think it is going to rain.
--- Watch out! He is going to hit that ball again.
---It's going to be a very interesting movie.
二、含if的真实条件句和虚拟条件句
（1）在英语中，语气是动词的一种形式，用来表示说话人的意图或态度。
英语的语气有三种：陈述语气（表示所说的话是事实），祈使语气（表示所说的话是请求或命令）和虚拟语气（表示所说的话只是一种主观的愿望或假设或建议等）。
如果所表示的条件是真实的，或者完全有可能实现的，叫真实条件句，主句和从句的谓语都用陈述语气。如：
If she doesn’t hurry up, she will miss the first bus.
如果所表示的条件不可能实现或者实现的可能性很小时，叫非真实条件句，主句和从句
If 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 wouldn’t 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 wouldn’t 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 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; wouldn’t be
B. had been ill; wouldn’t have been
C. had been ill; should have been
D. hadn’t 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; wouldn’t do
B. had been treated; wouldn’t have done
C. were treated; wouldn’t have done
D. had been treated; wouldn’t 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. doesn’t hear
B. didn’t hear
C. haven’t heard
D. hadn’t 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. shouldn’t do
B. didn’t do
C. hadn’t done
D. won’t do
10. I want to get back by 5 o’clock 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 clouds—there _____ 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 don’t 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, I’m 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 can’t 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. It’s so late. I don’t 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. don’t stop
B. didn’t stop
C. shall not stop
D. haven’t 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
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:
1—5 BAABB 6—10 DDCAC 11—15 CBACC 16—20 CCBCA
21—25 CABBC
26. 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 been friends for many years.
31. I don’t think it will rain this afternoon.
32. Will you lend me the car next week?
33. I won’t tell anybody what happened.
34. We are not going to stay there long.
35. I feel terrible. I think I’m going to be sick.
虚拟语气if假设句
一．分别对过去、现在和未来的假设 1、过去发生事情进行假设 这时从句动词用had done，主句用would/should/could/might+have done If you had worked harder, you would have passed your exam. If you had asked me, I would have told you. I would have been in bad trouble if Jane hadn’t helped me. If it hadn’t been for your help, we could have been in lots of trouble.(要不是你的帮助，我们要陷入很大的麻烦) 2、对现在情形进行假设 这时从句用did和were（be 动词都改成were），主句为would should/could/might+do If I knew her name, I would tell you. I would perfectly happy, if I had a car. If I were rich，I would spend all my time traveling. If my nose were a little shorter I’d be quite pretty. If it weren’t for the children, we could go skiing.要不是孩子们的原因，我们就会去滑雪 3、对将来情形假设 这时从句有以下三种动词形式 1.were/did 2.were to 3.should 主句为would/should/could/might+do看看下面的例子 What would I do if I were to lose/should lose/lost my job？ If you were to move your chair a bit, we could all sit down. if it should rain/were to rain/rained tomorrow, I would not go out. If they should play/were to play / played better next time , they would not fail again
if可以引导真实条件句和虚拟条件句
Unit 4 一. if 条件句 if可以引导真实条件句和虚拟条件句。真实条件句表示在假设的条件下，能够实现的情况。在这种情况下，主句和从句的谓语动语随各自的人称和时态发生变化，同时if条件句遵循“主将从现”的原则，即主句用一般将来时，从句用一般现在时表将来。 If it doesn’t rain tomorrow, we will go for a picnic. 如果明天不下雨，我们去野餐。 如果if条件句用来描述说话人认为与事实相反的内容，或仅是一种愿望，假设、猜测等，我们称为虚拟条件句。 If I got rich , I would travel around the world. 如果我有钱了，我将周游全世界。 1. —I often get nervous when I have an English class. What should I do?
—If I were you, I . (ask the English teacher for help) 2. —What would the earth be like if there ?(is no air or water on it) —It could be like the moon without any living things. 3. If it ,the crops would be saved. (is to rain tomorrow) 4. If we had found him earlier, we .(solve the problem more easily) 5. If I hadn’t been so busy, I .(take part in the party) 四、单选。 ( )1. If my father here now, he tell me what to do. A. were, would B. were, will C. is would D. is will ( )2. If I a bee, I work much harder. A. were, would B. were, shall C. had, will D. have, should ( )3. If I much money, I buy a house. A. have, will B. had, would C. had, will D. have, should ( )4. He learn more quickly if he harder. A. will, work B. would , worked C. would, work D. will, worked ( )5. If I you, I do that. A. was, wouldn’t were, wouldn’t C. am, won’t D. were, won’t ( )6. It’s quite impossible that it will rain tomorrow. But if it ,I would still go to the park. A. should rains B. would rain C. rained D. had rained 五、汉泽英 1. 如果我是你，我会帮助她。If I you, I her. 2. 如果我以前去过那个地方，我就认识路了。（和相反） If I to the place before, I the way. 3. 万一你明天迟到了，我们就不等你了。（和相反） If you tomorrow, we for you.=If you late tomorrow, we for you. 4. 如果没有空气，地球上就不存在生物。 If there no air, there no living things.
初中英语——If引导的条件状语从句(整理版)说课讲解
在句子中做条件状语的从句称为条件状语从句。引导条件状语从句的连接词有：if ,unless,as/so long as，once等 1.if引导的条件状语从句表示在某种条件下某事很可能发生。 If we pay much attention to the earth, we'll have a better world. 如果没有水会怎样？ 2.unless引导的条件状语从句You will fail in English unless you work hard. 3.as /so long as引导的条件状语从句So long as you're happy,i will be happy. 4.once引导的条件状语从句Once you begin,never stop. 提示：在条件状语从句中，用一般现在时代替一般将来时，用一般过去时代替过去将来时。Father told me if i worked hard he would buy me a gift. if 条件状语从句的时态练习 二、用所给词的适当形式填空 1.If you ________(feel) tired, you _______________ (have) to have a rest. 2. Where _______ he _________(see) the film if he ________________(have) time? 3. If there __________(be) fewer trees, there _______________( be) more pollution. 4. He _____________(dress) more casually if he ________________( not work) on weekends. 5. If Marcia _____________(live) alone, she ___________________( keep) a pet parrot. 6. Lana ________________( buy) a new dress if the old one ____________(be) out of style. 7.The twins ______________(fight) if they_______________(argue). 8. I ____________(have) a bake sale if I _____________(need) money for education. 9. Peter _____________( send) me a beautiful souvenir if he ________________(tour) Spain. 10. If Mr Green ___________(say) I am hard- working, my parents _________( feel) glad. 11.I ____________(go) to the beach if it________________ ( not rain) this week. 12. __________they __________( have) a match if the P.E. teacher _____________(be) busy? 13.He ____(write) a letter to his grandparents if he ____(get) his report card this week. 14. If she ____________(get) up late, she _____________ ( not catch) the early bus. 15. Peter ________(major) in English if he ____(pass) the exams in Peking University. 15.如果他到的晚了会发生什么事情？What _______________ if he _____________ late? 16. 如果努力学习，你就会取得好成绩。 If you__________ _________, you ___________ good _____________. 17. 他如果看电视太久了，他的父母会不高兴。 If he _________ TV too much, his parents __________ __________ unhappy. 18. 如果我们为他组织生日聚会，大家都会来的。 Everyone ________________ if we _____________ a birthday party __________ him. 19. 如果明天不下雨，我会和你一起去公园的。 If it __________ __________ tomorrow, I ______________ go to the park _________ you.
If条件句和虚拟语气
If条件句和虚拟语气 if 条件句和虚拟语气 包含条件从句的句子叫条件句。条件句有两类：一类是真实条件句（First conditional）,一类是非真实条件句(Second Conditional)。如果假设的情况是有可能发生的，就是真实条件句；如果是纯属假设情况或是不可能发生或可能性不大的情况，则是非真实条件句。 1.真实条件句,可用if和unless引导 1）一个动作发生，另一动作随之发生 I’ll lend Peter the money if he needs it. If he has time, he will come. If he doesn’t come before 12 o’clock, we won’t wait for him. I shall go tomorrow unless it rains. I won’t go to her party unless I am invited. 2）表示命令、建议或请求,这时的if等于when If she telephones, let me know. Give my love to Lawrence if you see him. 3)will用于if从句中，不表示将来，而表示愿意或坚持的意思 If you will come this way, I’ll take you to the manager’s office. If you will get drunk every night, it’s not surprising you feel ill. 2. 非真实条件句
非真实条件句包括虚拟条件句和错综时间条件句 1）虚拟条件句分三类，其结构列表如下： If I become president, I’ll make all of my people live a happy life. (竞选总统的候选人这样说) If I became president, I’d make all of my people live a happy life. (一个小学生这样说) l 以下与现在事实相反 He wouldn’t feel so cold if he were indoors. I am sorry I am very busy just now. If I hade time, I would certainly go to the movie with you. l 以下与过去事实相反 If you had come here a little earlier, you would have met the pop star. I don’t know what would have happened if Jane hadn’t been able to speak Japanese. l 以下推测将来 If I were to do the work, I should do it in a different way. If it should rain again, what else could we do? 2) 错综时间条件句
If条件句的虚拟用法练习
高中英语If条件句的虚拟用法练习 一、单项选择 1.If I had had enough time, I___ my work. A. would finish B. must have finished C. would have finished D. had finished 2.If there were no water in the world, everything ___. A. will die B. would die C. would have died D. would have been dead 3.If you had spoken clearly, you would___. A. understand it B. have understood C. be understood D. have been understood 4.If you ___ that late movie last night, you wouldn't be so sleepy. A. haven't watched B. hadn't watched C. didn't watch D. wouldn't have watched 5.If the doctor had been available, the child ___. A. would not die B. would not have died C. could not die D. must not have died 6.___ what was going to happen, I would never have left her alone. A. Had I known B. If I know C. If I knew D. If had I known 7.- --- “Where have you been?” ----- “I got caught in traffic; otherwise _____ sooner.” A. I would be here B. I have been here C. I had been here D. I would have been here 8.___ in your position, I would help him. A. Was I B. Were I C. If I am D. If I had been 9.Had he studied hard, he___ the exam. A. would pass B. could pass C. had passed D. would have passed 10.___, I would take an umbrella with me. A. Had I been you B. I were you C. Were I you D. I had been you 11. ---- I thought you would come back tomorrow. ---- I would if I ___ to attend a meeting. A. don’t have B. didn’t have C. will not have D. would not have 12.Ten minutes earlier, they ___ the plane. A. will catch B. would catch C. would have caught D. will have caught 13.I ___, but I was stopped by the heavy rain. A. mean to come B. meant to come C. had meant to come D. meant coming 14.If it were not for the fact that you _____ ill, I would ask you to do this right now. A. were B. had been C. are D. should be. 15. Had you listened to the doctor, you _____ all right now. A. are B. were C. would be D. would have been
if引导的条件句中的虚拟语气
if引导的条件句中的虚拟语气 虚拟语气表示一种不能实现的假设。该语法主要用于if条件状语从句。 一、if引导的条件状语从句的分类及虚拟条件句的判断 1、可以把条件句分为两类： 1).真实条件句（Sentences of Real Condition）：凡是假设的情况发生性可能很大，就是真实条件句。例如： ⑴、If I have time , I will help you with this work.如果我有时间会帮助你做此工作的。 (2)、If time permits, we'll go fishing together.(如果有时间的话，我们就一起去钓鱼。） 2).虚拟条件句（Sentences of Unreal Condition）：当假设是不大可能实现时，就是虚拟条件句。例如： ⑴、If I were you , I would have attended the meeting. 如果我是你的话，就去参加会议了。 ⑵、If he had come here yesterday, he would have seen h is old friend.假如他昨天来这儿的话，就会看见他的老朋友。 ⑴、If it had rained yesterday, we would have stayed at home.（如果昨天下雨的话，我们就会留在家里。） 2、.if条件状语从句中虚拟语气的判断 判断是真实条件句还是非真实条件句。只有在非真实条件句中才使用虚拟语气。通过句子意思，看假设的条件是否能够实现，能
够实现是真实条件句，不能使用虚拟语气；假设的条件不能实现则是非真实条件句，要用虚拟语气。 判断这个假设是与哪个事实相反。通常有三种情况：①与过去事实相反。②与现在事实相反。③与将来事实可能相反。 3、“后退一步法” 后退一步法是指在准确地判断了该句与哪一事实相反后，按虚拟语气的后退一步法处理从句谓语动词的时态。即：在非真实条件状语从句中，谓语动词按正常情况“后退一步”。也就是： ①与过去事实相反，在从句中用过去完成时形式表示。 ②与现在事实相反，在从句中用过去一般时形式表示。 ③与将来事实可能相反，在从句中用过去将来时形式表示。 主句中则用情态动词would, should, could 等加一个与从句一致的动词形式。例： ⑴、If I had come her yesterday, I would have seen him. ⑵、If I were a teacher, I would be strict with my stud ents. ⑶、If it should snow tomorrow, they couldn't go out. 4、注意事项 ①if条件句中如有were, should, had，可以省去if，并使用倒装语序。 ②在现代英语中if条件状与从句中的谓语动词如果是be其过去形式一般用were。
if引导的条件状语从句讲解和练习(答案)
t 条件状语从句 一、 条件状语从句通常由 if （如果）, unless （除非），as long as （只要）引导。 例如：If it rains tomorrow, we won ’go to the park. 如果明天下雨，我们就不去公园了。 Unless weather stops me, I go for a walk every. 我每天都会去散步，除非遇上坏天气。 Our parents will be pleased with our performance as long as we try our best. 小试牛刀：1、只要我们竭尽全力，父母就会满意我们的表现。 Our parents will be pleased with our performance _____ _____ ______ we try our best. 2、如果人人为保护环境做出贡献，世界将会变得更美好。______ ______ ______ _____ _______ to protecting the environment, the world will become much more beautiful. 二、if 引导的条件状语从句 （1）“if 从句+祈使句”的句子。其实，if 作为一个连词，主句也可以是其他形式的句子。 例如：If you want to go, please let me know. If the green light isn ’t on, wait for a minute. (2)“祈使句 + and (or)+ 陈述句” 在意思上相当于一个带有条件状语从句的复合句。 注意：A. “祈使句 + and + 陈述句”可以转化为 if 引导的肯定条件状语从句，而且主语是第二人称。 B. “祈使句 + or + 陈述句”可以转化为 if 引导的否定条件状语从句，而且主语是第二人称。 例如：Study hard and you will pass the exam. =If you study hard, you will pass the exam. Hurry up, or you ’ll be late. =If you don ’t hurry up, you ’ll be late. 考题 (2010 重庆中考)Work hard ，________ you may catch up with your classmates soon. A.or B.but C.and D.yet 思路解析：本句是“祈使句＋and”的句型，句意为“努力学习，你会很快赶上其他同学的”，and 在句中表示承接 关系，所以选 C 项。答案：C 黑色陷阱：本题的陷阱是句型，本句型区别于“祈使句＋or”，这个句型的含义是“……，不然的话/否则……”。 绿色通道：祈使句后面既可以加 and ，也可以加 or ，所以要全面分析句意，再作决定。 小试牛刀：用 if 连接下列句子 1、Go to bed early and you will have a good rest. 2、Hurry up, or you ’ll miss the bus. 三、if 从句与主句具有以下特点： 1．If 从句中用一般现在时，表示未来的一种条件，从句中可以加时间状语。 e.g.If yo u can’t come tomorrow, we can hold the party a little later.明天你如果不能来，我们可迟一点举行宴会。
if条件句的虚拟语气与倒装句课件
虚拟语气与倒装句（教师版） 什么是虚拟语气（subjunctive mood）? If I were you, I would not do like this. 要我是你，我就不会这样做 I wish I became a millionaire. 要是我是个百万富翁多好啊 口头解释上面两个例句后引出虚拟语气的概念 表示说的话不是真实发生，只是一种假设，主观愿望，猜测，建议等非真实的情况。今天主要讲在条件句中虚拟语气的使用情况 Q: 那是不是所有的条件句都用虚拟语气？这里可以提问同学，进行互动后给出正确答案一．分类 1. 真实条件句，表示的假设是有可能发生的，此时主句不用虚拟语气。 e.g. If I have time, I will do the homework. （口头解释分析这个句子） 2. 虚拟条件句，表示的是一种假象，与事实相反或不太可能会发生，那就要用虚拟语气 e.g. If I were you, I would do the homework. （口头解释分析这个句子） 二．用法 时态类型主句从句例句 与现在事实相反主语+would/should/could/ might+ do If+主语+did （be 动词用were） 1. If I were you, I should work hard. 2. The bedroom would be so clean if I had time. 与过去事实相反主语+would/should/could/ might + have done If+主语+had done 1. If I had finished my homework, I would have passed that test. 2. If I had left a little earlier, I would have caught the train.
if引导的虚拟条件句(20200509141756)
Subjunctive Mood Ⅰ. Listen to the songs and fill in the blanks Number one: If _______________, _____________so high That the only people near me Would be the pilots in the sky. And If _______________, _______ so gracefully Through the air so all mankind could see. If _______________ Number two: If ______________I'd never hear your voice again, ___________each thing you ever said And on those lonely nights I could think of them once more And keep your words alive inside my head If _______________I'd never hear your voice again Number three: If I ______________, I _______________ in your way So I'll go, but I know I'll think of you every step of the way And I will always love you I will always love you Number four: yeah if ___________, then money, fame and fortune never _____________ If ____________, _____________a party( it'd be ecstasy(狂喜)) yeah if __________ you y-y-y-y do y-y-y-y-y do y-y-y-y-y do If _____________ that would be the only thing I'd ever need Subjunctive mood is used to talk about situations that are ______ true or _____ likely to become true. Ⅱ Observe the following sentences and put them into throw groups 1.If it were Sunday tomorrow, I would go and see my friends. 2. If she hadn't called me, I could have overslept(睡过头) this morning. 3. If he were you, I might go and try. 4. If I had time right now, I should certainly help you. 5. If I had known your telephone number yesterday, I would have telephoned you. 6. If it should rain in the near future, the crops could be saved. 7. If he were here tomorrow, I should speak to him. 8. If we had no air and water, we wouldn't survive. 9. If it snowed tomorrow, I might stay at home. 10. If you were to be a millionaire soon, what would you do with your money? Contrary to the present:__________________ Contrary to the past:_____________________ Contrary to the future:___________________ Ⅲ Structures of subjunctive mood 1. 虚拟条件从句主句 与现在事实 相反的假设If+S+________________ S+_____________________ 与过去事实 相反的假设If+S+ ________________ S+_____________________ 与将来事实 相反的假设 _______________ If+ S+ _______________ _______________ S+_____________________ 2. If 的省略:________________________________________________ 3. 错综条件句:______________________________________________ 1)If you had followed my advice the other day, you would feel better now.
if条件句专项练习
If条件句练习 一、单项选择 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. wer e not ill; wouldn’t be B. had been ill; wouldn’t have been C. had been ill; should have been D. hadn’t been ill; could be 3. Alan ___ the party if he had gone to London. A. would have missed B. had missed C. would miss D. missed 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. Y oung _____ with justice, he _____ such a wrong thing. A. were treated; wouldn’t do B. had been treated; wouldn’t have done C. were treated; wouldn’t have done D. had been treated; wouldn’t 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. If I knew you were coming, I ___ you at the airport. A. had met B. met C. would meet D. would have met 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. shouldn’t do B. didn’t do C. hadn’t done D. won’t do 10. If only I ___ to my parents! (But I didn’t.) A. listened B. had listened C. should listen D. would listen 11. I ___ you some money, but I hadn’t got any then. A. would lend B. would have lent C. could lend D. may have lent 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
if引导的条件状语从句讲义及答案
if 引导的条件状语从句（讲义） 状语 用来表示行为发生的时间、地点、目的、方式、程度等，通常由 副词或介词短语充当，也可由一个句子充当。 I slept at home yesterday because I had a bad cold. 状语从句 状语从句指句子作状语。 根据其作用可分为时间、地点、原因、条件、目的、结果、让步、 方式等从句。 状语从句一般由连词（从属连词）引导。 I will go to school by bike tomorrow if it is sunny. Grammar focus —I think I ' ll take the bus to the party. —If you do, you ' ll be late. If you take the bus to the party, you —I think I ' ll stay at home. —If you do, you ' ll be sorry. If you stay at home, you ' ll be sorry. —What will happe n if they have the party today? ——If they have it today, half the class won —Should we ask people to bring food? —If we ask people to bring food, they and chocolate. 1 if 在本单元句中意为“ _______________ ； _______ ”，用于引导 即if 引导的是一个完整的句子，所以一定要有主谓，成为从 句，另一个句子则成为主句。 If you go there, I ' ll go, too. We will go hiking if it doesn ' t rain tomorrow. If Bob leaves tomorrow, I will hold a party for him toni ght. 2 if 引导的条件状语从句既可以放在主句前，也可放在主句后。 但是如果放在主句前，即句首时，从句后面要用 与主句 隔开。 You will keep healthy if you do more exercise. If you do more ll be late. t come. ll just bring potato chips
if条件句和should的用法
If 引导条件句的用法 1、真实条件句用于陈述语气，假设的情况可能发生，其中if 是如果的意思。时态关系 句型：条件从句主句 一般现在时shall/will + 动词原形 If he comes, he will bring his violin. 典型例题 The volleyball match will be put off if it ___. A. will rain B. rains C. rained D. is rained 答案B。真实条件句主句为将来时，从句用一般现在时。 注意： 1）在真实条件句中，主句不能用be going to表示将来，该用shall, will. (错) If you leave now, you are never going to regret it. (对) If you leave now, you will never regret it. 2）表示真理时，主句谓语动词便不用shall (will) +动词原形，而直接用一般现在时的动词形式。 2 非真实条件句 1）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。 句型：条件从句主句 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。 句型：条件从句主句 过去完成时should(would) have+ 过去分词 If she had worked harder, she would have succeeded. The rice would not have been burnt if you had been more careful. If my lawyer had been here last Saturday, he would have prevented me from going. If he had come yesterday, I should / would have told him about it. 含义：He did not come yesterday, so I did not tell him about it. If he had not been ill and missed many classes, he would have made greater progress. 含义：He was ill and missed many lessons, so he did not make greater progress. c. 表示对将来的假想 句型：条件从句主句 一般过去时should+ 动词原形 were+ 不定式would + 动词原形 should+ 动词原形
if条件句讲解及练习
i f条件句讲解及练习
IfIwereyou,Iwouldnotletoutthesecret. 如果我是你的话，我不会泄露这个秘密的。 IfIknewhisnewaddress,Iwouldtellyou. 如果我知道他的新地址，我会告诉你的。 Ifhestudiedharder,hewouldpasstheexam . 如果他学习再努力点的话，他会通过考试的。 Ifwehadmadefullerpreparation,weshoul dhavewonthegame. 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。
Ifyouhadtakenmyadvice,you wouldn’tha vebeenlateforthemeeting. 如果你听了我的建议，你开会就不会迟到了。 Ifshewereto/shouldcome,Iwouldtellherth esecret. 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： WereIyou,Iwouldnotletoutthesecret. Hadwemadefullerpreparation,weshould havewonthegame.
Had youtakenmyadvice,youwouldn’thav ebeenlateforthemeeting. Shouldshecome,Iwouldtellherthesecret. 高一语法练习（四）预测、if条件句及虚拟语气 一、单项选择 1.IfI_____wherehelived,I_____anotetohi m. A.know,wouldhavesent B.hadknown,wouldhavesent C.know,wouldsend D.knew,wouldhavesent 2.Maryisilltoday.Ifshe_____,she_____ab sentfromschool. A.werenotill;wouldn’tbe B.hadbeenill;wouldn’thavebeen