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虚拟语气if的三种用法教案-范文模板及概述示例1:标题：虚拟语气if的三种用法教案引言：虚拟语气if是英语语法中的一个重要概念。
它用于描述虚拟的情况或假设，与实际情况相反或不可能实现的情况。
在本文中，我们将介绍虚拟语气if的三种常见用法，并提供相关教学案例。
一、虚拟语气if表示对过去情况的假设1. 如果现在完成时表示过去的假设例如：If I had studied harder, I would have passed the exam.（如果我当时更努力学习，我就能通过考试。
）2. 如果过去完成时表示过去情况的假设例如：If you had told me earlier, I would have helped you.（如果你早点告诉我，我就会帮助你。
）教学案例：让学生完成以下句子，使用虚拟语气if表示对过去情况的假设：1. 如果他没有错过公交车，他就不会迟到了。
2. 如果我看到那本书，我就会告诉你。
3. 如果我知道你的生日，我就会为你准备礼物。
二、虚拟语气if表示对现在情况的假设1. 如果一种不可能实现的现实情况例如：If I were a bird, I would fly around the world.（如果我是一只鸟，我就会飞遍全世界。
）2. 如果一种与实际情况相反的情况例如：If it wasn't raining, we would go for a walk.（如果不下雨，我们就会去散步。
）教学案例：让学生完成以下句子，使用虚拟语气if表示对现在情况的假设：1. 如果我有超能力，我会帮助所有需要帮助的人。
2. 如果我有时间，我会去旅行。
3. 如果我不生病，我就会参加派对。
三、虚拟语气if表示对将来情况的假设1. 如果将来某种情况不会发生例如：If it doesn't rain tomorrow, we will have a picnic.（如果明天不下雨，我们将去野餐。
if虚拟语气如果虚拟语气虚拟语气是一种表示假设、愿望、建议或怀疑的语气。
它在语法上与事实不符，因此需要特殊的动词形式或特定的句子结构来表达。
在本文中，我们将探讨虚拟语气的基本用法、形式和相关注意事项。
虚拟语气广泛应用于日常交际、文学作品、新闻报道等中，因此对于学习者来说，掌握虚拟语气是非常重要的。
1. 表达假设或条件虚拟语气用来表达对于过去或现在的假设或条件，它使用"if"加上过去完成时、过去时或过去将来时的动词形式。
例如：- 如果我是你，我会去旅行。
(If I were you, I would travel.)- 如果我有更多时间，我会看更多的书。
(If I had more time, I would read more books.)- 如果你不去，我也不会去。
(If you didn't go, Iwouldn't go either.)2. 表达愿望或建议虚拟语气还用来表达愿望或建议，常常使用词组"would rather"、"had better"等。
例如：- 我希望我会弹钢琴。
(I wish I could play the piano.)- 我宁愿你不要告诉他。
(I would rather you didn't tellhim.)- 你最好给他打个电话。
(You had better give him a call.)3. 表达怀疑或推测虚拟语气还用来表示对于事实的怀疑或推测，常用的动词有"suppose"、"imagine"、"guess"等。
例如：- 我想象不出他会这样做。
(I can't imagine he would do such a thing.)- 我猜他可能会迟到。
(I guess he might be late.)- 假设他赢了比赛，我们该怎么办？(Suppose he wins the game, what should we do?)虚拟语气在英语中有着重要的语法和语义作用，但需要注意的是，虚拟语气在现代英语中的使用逐渐减少，特别是在口语中。
if三大虚拟语气公式数码科技日新月异，从电子杂志、DVD剧集到优酷、全民K歌，科技应用融入人们的生活，带来乐趣和便利。
让我们来关注一下，虚拟语气在科技应用中所起到的重要作用。
虚拟语气是一种遣词造句的方法，也是表达虚拟的能力的最佳方式，用于表达某些虚拟的情况而又不把它们看出实情形式，通过虚拟语气来实现它们。
在虚拟语气中，常用的虚拟语气公式有：第一类虚拟语气公式：were + to + do，意思是假如或是要是……例如，当我们将要分享产品信息到社交网络时，我们可以使用：If we were to share the product information to social networks，来表达“假如去分享产品信息到社交网络时”的虚拟情况。
第二类虚拟语气公式：had + done，意思是假如或是要是曾经……例如，当我们要表达“假如之前曾经采取措施”的虚拟情况时，可以使用：If we had taken measures，来表达这种情况。
第三类虚拟语气公式：should + do，意思是假如或是要是处于一定情况下应该……例如，当我们要表达“假如处于一定条件下应该采取措施”的虚拟情况时，可以使用：If we should take measures，来表达这样的虚拟情况。
显然，虚拟语气的应用在科技应用中有着重要的作用。
在软件开发方面，虚拟语气用于表示一定条件下所作出的决策，这样可以将程序流程更加清晰并且更有可控性。
例如，在对某一对象进行某一操作之前，若其状态不处于期望状态，则可以利用should do的形式来表达：If the status of the object is not in the expected state, it should not be operated.此外，虚拟语气也被广泛运用于网络技术。
虚拟语气可以用来表达某种可能的情况和未来的发展趋势，使得用户可以提前了解并做出具体的调整。
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 his 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。
英语动词有三种语气：陈述语气、祈使语气、虚拟语气（用来表示说的话不是事实,或者是不太可能发生的情况,而是一种愿望，建议，假设的语气叫虚拟语气。
）虚拟语气的考点：1.条件句中的虚拟语气的用法；2.条件句中虚拟语气的倒装;3.名词性从句中虚拟语气的用法;4.几种特殊结构中虚拟语气的用法；5.虚拟语气时态的判定。
一、If引导的虚拟条件句区别:If it rains tomorrow,the crops will be saved. 陈述语气If it rained tomorrow，the crops would be saved。
虚拟语气真实条件状语从句与非真实条件状语从句真：eg 。
If he doesn't hurry up, he will miss the bus.如果他不快点，他将错过巴士.( 真实条件状语)（不是虚拟语气）If he is free，he will ask me to tell stories.如果他是空闲的，他会要求我讲故事。
（真实条件状语)（不是虚拟语气)非真:eg。
If I were you，I would go at once。
如果我是你,我马上就会去。
(非真实条件状语从句）二、虚拟语气在条件从句中：【例句】1。
If you had come a few minutes earlier，you would have met him。
要是你早来几分钟的话，你就能见到他了。
（与过去事实相反）2.If it were sunny tomorrow,i would come to see you.明天要是天气好的话，我来看你。
（与将来事实可能相反）3.If i were you,i would go at once.假如我是你的话,我会马上走.（与现在事实相反，事实上我不可能是你）主从句的谓语形式（一)与现在事实相反的虚拟条件句表示与现在事实相反的情况，例1。
If I were you, I would take an umbrella.如果我是你,我会带把伞。
if虚拟语气用法虚拟语气（Subjunctive Mood）是英语中的一种语气，用于表示假设、建议、愿望、怀疑等非现实的情况。
在if虚拟语气用法中，通常有以下几种情况：1. 对现在或将来的假设：- 如果我是国王，我会做很多好事。
（If I were a king, I would do many good things.）- 如果我是你，我会去旅行。
（If I were you, I would travel.）2. 对过去的假设：- 如果我昨天赢了彩票，我就会买一辆新车。
（If I had won the lottery yesterday, I would have bought a new car.）- 如果我早点知道这个消息，我就不会错过那个会议了。
（If I had known this news earlier, I wouldn't have missed that meeting.）3. 建议、要求或命令：- 如果你能帮我一下，我会非常感激。
（If you could help me, I would be very grateful.）- 如果他不来参加会议，我们就取消吧。
（If he doesn't come to the meeting, let's cancel it.）4. 愿望、希望或遗憾：- 要是我能飞就好了。
（If only I could fly.）- 要是我昨天没生病就好了。
（If only I hadn't been sick yesterday.）5. 建议或要求某人做某事：- 如果你愿意的话，请帮我一个忙。
（If you would like to, please do me a favor.）- 如果他不介意的话，让他来参加我们的聚会吧。
（If he doesn't mind, let him come to our party.）。
If虚拟语气在if引导的条件句中的用法三点：从句（条件）主句（目的）例句表示于现在事实相反的虚拟条件句If+主语+动词的过去式（be用were）主语+would(shouldcould might)+动词原型If he were free, he would help us. 要是他有空的话，它会帮助我们的。
表示与过去事实相反的拟条件句If+主语+had+动词的过去分词主语+would（shouldcould might）+have+动词的过去分词If I had seen the film, I would havetold you about it. 我如果看过这场电影，我会把电影内容告诉你了。
表示与将来事实相反的虚拟条件句If+主语+should（wereto）+动词原型/动词的过去式主语+would（couldshould might）+动词原型If he were to come here, he wouldtell us about it. 如果他要来的话，他会通知我们一声引导真实条件状语从句引导真实条件状语从句（虚拟语气）与将来事实相反的虚拟语气请看下面的题目：If we __________ 200 years old，we __________ everything.A. were to be，could changeB. had been，changedC. were，would have changedD. should be，changed该题考查与将来事实相反的虚拟语气，此时的主句谓语通常用would(should，could，might)＋动词原形，而从句谓语可能有以下几种情况：1.从句谓语用过去式：If your father knew this，he would be angry. 要是你父亲知道了，他会生气的。
If it rained tomorrow，the sports meet would be put off. 要是明天下雨，运动会就推迟。
高二英语虚拟语气if的知识点虚拟语气是英语语法中的一个重要概念，表示对事实或真实情况的否定、怀疑、猜测、建议、要求等含义的一种语法形式。
在虚拟语气中，if引导的条件从句常常是重要的一种形式。
本文将介绍高二英语学生需要了解的虚拟语气if的知识点，以帮助学生更好地理解和运用该语法形式。
一、虚拟语气的概念虚拟语气基于与现实相反或不可能实现的假设，用来表示想象、假定、建议、命令等语义。
它又可分为虚拟现在、虚拟过去和虚拟将来三种形式。
二、虚拟语气if的用法1. 虚拟条件句的基本结构虚拟条件句通常由if引导，包括一个条件从句和一个主句。
条件从句使用了虚拟语气，主句则表达对条件从句中情况的可能性、愿望、建议等态度。
2. 虚拟语气if的条件从句虚拟语气的条件从句有以下几种形式：（1）与现在事实相反的虚拟语气a. If + 主语 + 过去式，主语 + would/could/should/might + 动词原形。
b. If + 主语 + were，主语 + would/could/should/might + 动词原形。
（2）与过去事实相反的虚拟语气a. If + 主语 + had + 过去分词，主语 + would/could/should/might + have + 过去分词。
b. If + 主语 + had + V-ed，主语 + would/could/should/might + have + V-ed。
（3）表示对现在或将来的怀疑、猜测a. If + 主语 + should + 动词原形，主语 +would/could/should/might + 动词原形。
b. Were + 主语 + to + 动词原形，主语 +would/could/should/might + 动词原形。
3. 虚拟语气if的主句虚拟语气if的主句可以用于表示愿望、建议、可能性等。
（1）表示愿望a. 主语 + would like/love/wish + to + 动词原形。
英语动词有三种语气：陈述语气、祈使语气、虚拟语气（用来表示说的话不是事实，或者是不太可能发生的情况，而是一种愿望，建议，假设的语气叫虚拟语气。
）虚拟语气的考点：1.条件句中的虚拟语气的用法；2.条件句中虚拟语气的倒装；3.名词性从句中虚拟语气的用法；4.几种特殊结构中虚拟语气的用法；5.虚拟语气时态的判定。
一、If引导的虚拟条件句区别：If it rains tomorrow，the crops will be saved. 陈述语气If it rained tomorrow，the crops would be saved. 虚拟语气真实条件状语从句与非真实条件状语从句真：eg.If he doesn’t hurry up,he will miss the bus.如果他不快点，他将错过巴士。
(真实条件状语)（不是虚拟语气）If he is free,he will ask me to tell stories.如果他是空闲的，他会要求我讲故事。
（真实条件状语）（不是虚拟语气）非真：eg.If I were you,I would go at once.如果我是你，我马上就会去。
（非真实条件状语从句）二、虚拟语气在条件从句中：【例句】1.If you had come a few minutes earlier，you would have met him.要是你早来几分钟的话，你就能见到他了。
（与过去事实相反）2.If it were sunny tomorrow，i would come to see you.明天要是天气好的话，我来看你。
（与将来事实可能相反）3.If i were you，i would go at once.假如我是你的话，我会马上走。
（与现在事实相反，事实上我不可能是你）主从句的谓语形式（一）与现在事实相反的虚拟条件句表示与现在事实相反的情况，例1.If I were you,I would take an umbrella.如果我是你，我会带把伞。
（事实：我不可能是你）2.If I knew his telephone number,I would tell you.如果我知道他的电话号码，我就会告诉你。
（事实：不知道）3.If there were no air or water,there would be no living things on the earth.如果没有水和空气，地球上就不会有生物。
(事实：地球上既有空气也有水)4.If I had any money with me,I could lend you some.如果我带钱了，我就会借给你些。
（事实：没带钱）5.If he studied harder,he might pass the exam.如果他再努力些，就能通过考试了。
（事实：没有努力If+主+did（were），主+would/should/could/might+动词原形（二）与过去事实相反的虚拟条件句例：1.If I had got there earlier,I should/could have met her.如果我早到那儿，我就会见到她。
（事实：去晚了）2.If he had taken my advice,he would not have made such a mistake.如果他听我的劝告的话，就不会犯这样的错误了。
（事实：没有听我的话）If+主+had done sth，主+would/should/could/might+动词完成式（have done）（三）表示对将来情况的主观推测例：1.If he should come here tomorrow,I should/would talk to him.如果他哪天来这儿的话，我就跟他谈谈。
（事实：来的可能性很小）2.If there were a heavy snow next Sunday,we would not go skating.如果下周日下大雪，我们就不能去滑冰了。
（事实：不知能否下雪）3.If she were to be there next Monday,I would tell her about the matter.如果她下周一来这儿的话，我就会告诉她这件事的始末。
If+主+did（were to/should do），主+would/should/could/might+动词原形（在表示建议、命令、要求等含义的宾语从句，谓语动词常用虚拟语气，"should＋动词原形"构成，should可省略。
）（四）有时，主句和条件状语从句的谓语动作若不是同时发生时，虚拟语气的形式应作相应的调整①从句的动作与过去事实相反，而主句的动作与现在或现在正在发生的事实不符。
如：If I had worked hard at school,I would be an engineer,too.如果我在学校学习刻苦的话，我现在也会成为一个工程师了If they had informed us,we would not come here now.如果他们通知过我们的话，我们现在就不会来这里了。
②从句的动作与现在事实相反，而主句的动作与过去事实不符。
如：If he were free today,we would have sent him to Beijing.如果他今天有空的话，我们会已经派他去北京了。
If he knew her,he would have greeted her.要是他认识她的话，他肯定会去问候她了。
③从句的动作与过去发生的情况相反，而主句的动作与现在正在发生的情况相反。
如：If it had not been raining too much,the crops would be growing much better.如果天不下太多的雨的话，庄稼会长得更好。
If he had been working hard,he would be working in the office now.要是他一直努力工作的话，他现在已进了办公室了。
（五）if虚拟句的倒装当虚拟条件句的谓语动词含有were,should,had时，if可以省略，这时条件从句要用倒装语序，即将were,should,had等词置于句首，这种多用于书面语。
如：Should he agree to go there,we would send him there.要是他答应去的话，我们就派他去。
Were she here,she would agree with us.如果她在这儿的话，她会同意我们的。
Had he learnt about computers,we would have hired him to work here.如果她懂一些电脑知识的话，我们已经聘用他来这里工作了。
如果条件状语中有were，had，should时，可以倒装成：were/should/had+主+其他If i were you，i would try it again. 如果我是你，我会再试一次。
Were i you,…If he had been there yesterday，he would have seen the film.Had he been there yesterday,…If it should snow tomorrow,we wouldn’t go out.Should it snow tomorrow,…（六）非真实条件句中的条件从句有时不表达出来，只暗含在副词、介词短语、上下文或其他方式表示出来，这种句子叫做含蓄条件句，在多数情况下，条件会暗含在短语中，如without ….,but for….等But for his help,we would be working now.要不是他的帮助，我们还会在工作呢。
Without your instruction,I would not have made such great progress.要是没有你的指导，我不会取得如此大的进步。
We didn’t know his telephone number;otherwise we would have telephoned him.我们不知道他的电话号码，否则我们就会给他打电话。
（七）有时，虚拟条件句中，主、从句可以省略其中的一个，来表示说话人的一种强烈的感情。
①省略从句He would have finished it.他本该完成了。
You could have passed this exam.你应该能通过这次考试了。
②省略主句If I were at home now.要是我现在在家里该多好啊。
If only I had got it.要是我得到它了该多好啊。
1. the exam，he would have attend a college.A.If he passedB.Had he passedC.Were he passedD.If he should pass2. five minutes earlier，you could have seen them off.A.If you should arriveB.If you arriveC.Had you arriveD.Should you arrive翻译句子：1.If___________________(如果明天不下雨的话),we will go to the zoo.2__________________(如果你生病了),you must see the doctor.3.You’ll have to have a rest_______________（如果你感到累）4．___________________(如果我们训练海豚),they perform tricks.5．Parrots repeat words_______________________(如果你教他们)6．_____________(如果老虎住在野外),they will hunt for their own food.7.If you do not hurry up,________________________________.(你会上学迟到).练习以及解析1.I enjoyed the movie very much.I wish I_____the book from which it was made.A.have readB.had readC.should have readD.are reading2.You are late.If you_____a few minutes earlier,you_____him.A. come;would meetB.had come;would have mete;will meetD.had come;would meet3.The two students talked as if they_____friends for years.A.should beB.would beC.have beenD.had been5.He looked as if he_____ill for a long time. A.was B.were C.has been D.had been7.I wish that I_____with you last night.A.wentB.could goC.have goneD.could have gone9.I cant stand him.He always talks as though he_____everything.A.knewB.knowsC.has knownD.had known10._____the fog,we should have reached our school.A. Because ofB.In spite ofC.In case ofD.But for11.If you had told me in advance,I_____him at the airport.A.would meetB.would had metC.would have metD.would have meet12.Mike can take his car apart and put it back together again.I certainly wish he_____me how.A.teachesB.will teachC.has taughtD.would teach16.He suggested that they_____use a trick instead of fighting.A.shouldB.wouldC.doD.had17.My father did not go to New York;the doctor suggested that he_____there.A.not wentB.won’t goC.not goD.not to go19.Would you rather I_____buying a new bike?A.decided againstB.will decide againstC.have decidedD.shall decide against20.You look so tired tonight.It is high time you_____.A.go to sleepB.went to sleepC.go to bedD.went to bed21.—Why didn’t you buy a new car?－I would have bought one if I_____enough money.A. hadB.have hadC.would haveD.had had22.If she could sew,_____.A.she make a dressB.she would have made a shirtC.she will make a shirtD.she would had made a coat24.His doctor suggested that he_____a short trip abroad.A.will takeB.would takeC.takeD.took25.The Bakers arrived last night.If they’d only let us know earlier,_____at the station.A.we’d meet themB.we’ll meet themC.we’d have met themD.we’ve met them26.If I_____you,I_____more attention to English idioms and phrases.A.was;shall payB.am;will payC.would be;would payD.were;would pay27.We might have failed if you_____us a helping hand.A.have not givenB.would not giveC.had not givenD.did not give28.The law requires that everyone_____his car checked at least once a year.A.hasB.hadC.haveD.will have29.It is strange that he_____so.A.would sayB.would speakC.should sayD.will speak30.Had I known her name,_____A.or does she know mine?B.and where does she live?C.she would be beautiful.D.I would have invited her to lunch.翻译句子：1.it doesn't rain tomorrow2.If you are ill3.if you feel tired4.If we train dolphins5.if you te ach them6.If tigers live in the wild7.you will be late for school1—5BBDD6—10DAD11—15CD 16—20ACAD21—25DBCCC26—30DCCCD31—35DDCCB36—40DCACD解析：1.wish后面用虚拟语气，表示与过去事实相反用过去完成时。
