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虚拟语气的用法
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这个问题太大。在新概念二册六十四课很具体体现，简单说吧：1.If型虚拟语气--分三种，与过去、现在和将来事实相反的句式不同，具体的句式-- &If sb. did, sb. would do（现在）； If sb. had done, sb. would have done（过去）； &If sb. were to do, sb. would do（将来），当然，这个是基本的常用句型，还有其他的形式，见到一个解决一个即可2.关键词虚拟--当你看到“wish”&if only&等等含有悔恨或希望的含义的词时，也可以由虚拟语气表达，动词变化形势和第一条一样---I wish I were a girl就是与现在事实相反的虚拟语气，动词的变化就是--时态向过去推（与现在相反变过去时）3.suggest/insist等表示建议和请求的词--他们的用法就是后面加从句：sb. suggest that sb. (should) do，should通常省略--The manager suggests that a tree planted here.--经理建议这个地方应该种棵树，should被去掉，后面不变。当然，这是一个非常庞大的语法结构，以上我认为是基础的部分你可以先掌握一些
同学你好，楼下两位老师对虚拟语气的回答已经非常全面了，你可以进行参考学习。如果你对虚拟语气等语法现象不是很了解，帮你推荐一本新概念二册的教材，全面解决你的语法问题，帮你搭建语法框架，通过练习进行巩固，加油！
AHe has published quite a number of essays this year .B) Wait outside until you are asked . Let's just take a break, shall we ? C) I wish you were more careful .If I had more money, I would buy a bigger apartment.Would you mind shutting the door ?
If I had time, I would certainly join you in the tennis match. If I were you, I would put her suggestion into account.If I hadn't been caught by something, I would have come to your party yesterday.()If he had taken my advice, he might not have made such a bad mistake.If I should have a chance to try it, I would do it in another way. Even if they were to fail, they wouldn't lose courage.
BEwereShould / would +
had + would / should + have +1) should + 2) were + 3) BEwerewould / Should + 1. If1hadshouldwerehadshouldwereifIf you were the manager here, what would you do?Were you the manager here, what would you do? If he should act like that again, he would be fired immediately. Should he act like that again, he would be fired immediately. 2) ifWithout air, there would be no life on the earth. But for your help, the little boy would have been drowned. We could have done the work better in that case. 3) ififHe would have come to see you earlier but he just came back from his business trip .but he just came back from his business tripBut that you helped me, I would have failed in the experiment. But that you helped me2. 1It + be +/
+ that/ that&should + &&&/ essential, important, advisable, desirable, imperative, natural, necessary, regretful, strange, proper, urgent, duty, a pity, no wonder, a regret, It is strange that he ( should ) say so .It is a great pity that you ( should ) think so . It is natural that a bird ( should ) rest in trees . It is necessary that he be sent to Beijing right away.
It is ordered that () , & It is proposed that () It is desired that
() , & & &It is requested that
()It is suggested that
() , & & &It is recommended that ()It is demanded that () , & & & It is decided that ()It is arranged that
() It is ordered that all the troops (should) withdraw three miles away.It is arranged that he leave for Canada on Friday. It is suggested that the English evening be held on Saturday. 2)&should + &&&command, demand, desire, insist, order, propose, recommend, request, require, suggestHe proposed that we ( should ) set a dead line for the complement of the plan .They requested that we ( should ) send a delegation to their country. I suggested that he ( should ) set off for our headquarters straightaway .wishwould rather / sooner that
------- --- ---, wishI wish that I knew something about programming.I wished that I knew something about programming.They wish that they hadn't said it to us.They wished that they hadn't said it to us.I wish that you would get younger and younger .The manager would rather that his secretary went to the meeting instead of him .He would sooner that he hadn't born until ten years ago .3) &should + &&& idea, suggestion, motion, proposal, order, recommendationadvice () , instruction ()The instruction was that nobody be allowed to go to sleep until further orders.My suggestion is that he leave for London at once . What do you think of his proposal that we ( should )put on a play at the English evening? ,4) &should + &&&as if as though, wishHe took his umbrella with him lest it rain. I'll keep a seat for you in case you should change your mind. They burned all the important documents for fear that they fall into the enemy's hands. Though everyone desert you, we will not .As long as a volume hold together, We don't care much about its outer appearance .This, if the news be true, will mean a lot to us. I can still remember the whole thing in great detail as though it were yesterday.They are talking as if they had been friends for years. 5) It is (high) time thatthat&&&&It is time that we got ready for the final examination.It is high time that we had our lunch. It is time that he made up his mind. 6) If only&If only&&&&&wishIf only she could understand my real feelings. If only my mother had survived the disease and lived till now. If only he would fine a satisfactory job after his graduation. 3. Could you tell me the way to the nearest shopping center ? Would you mind lowering your voice? Perhaps you could get better results this way .Which seat might I take? &&&may + &()God bless you!
&So be it then! May the friendship between our two peoples last forever.Come what may, we'll solve the problem by ourselves. 4.If the boy hadn't been saved this afternoon, his family would not be in peace now .If the machine were in good conditions, we would have used it in our last experiment. If you were to visit Hainan in two days, I could arrange some of my friends there to meet you at the airport. <span style="font-family:
一、 条件句中的虚拟语气1. 条件句中虚拟语气的形式从句中提出一种与客观现实不相符或根本不可能存在的条件，主句会产生的一种不可能获得的结果。条件句中的虚拟语气根据不同的时间有三种不同的形式。时间 & 从句谓语形式 & 主句谓语形式 & 将来 & 动词过去式(be用were)should + 动词原形were to + 动词原形 & would / should / might / could + 动词原形 & 现在 & 动词过去式(be 用 were) & would / should / might / could + 动词原形 & 过去 & had +动词过去分词 & would / should / might / could have + 动词过去分词 &
& & & 2. 条件句中的虚拟语气的举例(1) 将来时的条件句中的虚拟语气。如：If he should go to Qing Hua University, he would make full use of his time. 如果他要上清华大学的话，他就会充分利用他的时间了。If he were to come here, he would tell us about it. 如果他要来的话，他会通知我们一声。(2) 现在时的条件句中的虚拟语气。如：If he were free, he would help us. 要是他有空的话，它会帮助我们的。If he studied at this school, he would know you well. 如果他在这所学校学习的话，它会对你很熟悉。(3) 过去时的条件句中的虚拟语气。如：If I had seen the film, I would have told you about it. 我如果看过这场电影，我会把电影内容告诉你了。If I had got there earlier, I would have met Mr. Li. 如果我早点到那儿，我就会会到了李先生。3. 运用条件句中的虚拟语气时，须注意的几个问题(1) 当从句的主语为第三人称单数时，谓语动词若是系动词be时，可用 was 代替 were。但在倒装虚拟结构及 if I were you, as it were 中，只能用 were。如：Were I ten years younger, I would study abroad. 要是我还年轻十岁的话，我会去国外学习。If I were you, I would try my best to grasp the chance. 要是我是你的话，我要尽力抓住这次机会。(2) 有时，虚拟条件句中，主、从句的动作若不是同时发生时，须区别对待。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，我现在也会使工程师了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，庄家会长得更好。If he had been working hard, he would be working in the office now. 要是他工作一直努力的话，他现在已进了办公室了。(3) 当虚拟条件句的谓语动词含有 were, should, had 时，if 可省略，而将 were, should, had等词置于句首。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，我们会已经聘用他来这里工作了。(4) 有时，句子没有直接给出假设情况的条件，而须通过上下文或其他方式来判断。如：I would have come to see you, but I was too busy. 我本该来看你了，然而我太忙了。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。(5) 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. 你应该会通过这次考试了。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。二、其他状语从句的虚拟语气1. 目的状语从句中的虚拟语气(1) 在 for fear that, in case, lest 引导的目的状语从句中，若用虚拟语气时，从句谓语为： should + 动词原形。并且 should 不能省略She examined the door again for fear that a thief should come in. 她又把门检查了一遍，以防盗贼的进入。He started out earlier lest he should be late. 他很早就出发了以防迟到。(2) 在 so that, in order that 所引导的目的状语从句中，从句中的谓语为：can / may / could / might / will / would / should + 动词原形。如：He goes closer to the speaker so that he can hear him clearer. 他走近说话的人以便能挺得更清楚。He read the letter carefully in order that he should not miss a word. 他把信读得很仔细以便不漏掉一个单词。2. 让步状语从句中的虚拟语气(1) 在 even if, even though 所引导的让步状语从句中，可用虚拟语气，主句、从句的结构与 if 所引导的条件从句结构相同。如：Even if he were here himself, he should not know what to do. 即使他亲自来也不知该怎么办。Nobody could save him even though Hua Tuo should come here. 即使华佗在世也救不了他。(2) 在whatever, whichever, whenever, whoever, wherever, however, no matter wh-word 等引导的让步状语从句中，从句虚拟语气结构为：①may +动词原形(指现在或将来)。如：We will finish it on time no matter what / whatever may happen. 不管发生什么事，我们都要按时完成。We will find him wherever / no matter where he may be. 无论他在哪里，我们都要找到他。I will wait for him no matter how late he may come. 不管他来的多么晚，我都会等他。②may +完成式(指过去) ，主句结构不限。如：You mustn’t be proud whatever / no matter what great progress you may have made. 不管你取得了多么大的进步，你也不能骄傲。We must respect him no matter what / whatever mistakes he may have made. 不管他翻过什么错误，我们必须尊敬他。(3) 在though, although等引导的让步状语从句中，从句虚拟语气结构为 should +动词原形，主句结构不限。如：Although / Though he should often be late, he is a good student. 尽管他经常迟到，他还是个好学生。Although / Though he should be secretary, he must obey the rules. 尽管他是书记，他也必须遵守规定。3. 方式状语从句中的虚拟语气as if, as though 引导的方式状语从句常用虚拟语气。虚拟语气的结构为：表示所发生的时间 & 虚拟语气结构 & 发生在主句动作之前 & had + 过去分词 & 与主句动作同时发生 & 过去时(be 用were ) & 发生在主句动作之后 & would / could / might / should+原形动词 & 例如：They began to talk warmly as if they had known each other for long. 他们开始热烈的谈论起来就好像他们已相互认识很久了。He coughed twice as if someone should come. 他咳嗽两声就好像有人要来了。4. 原因状语从句中的虚拟语气amazed, angry, annoyed, astonished, disappointed, frightened, happy, pleased, proud, sorry, surprised, upset 等后面的状语从句中常用虚拟语气。其虚拟语气的结构为：①should + 原形动词(指现在或将来)。如：He was angry that you should call him by name. 他很生气，你竟然对他直呼其名。I was astonished that he should not answer such an easy question. 我很惊讶他竟答不出如此简单的问题。②should + 完成式, 指过去。如：I’m very sorry that you should have failed the exam. 我很遗憾，你这次考试竟然失败了。I was very surprised that Father should have known what I did yesterday. 我很吃惊，父亲竟指导我昨天所作的事情。三、宾语从句中的虚拟语气1．英语中，如：advise, ask, demand, desire, decide, insist(坚决要求) , order, propose, request, suggest(建议) 表示请求、要求、命令或建议等意义的动词所接的宾语从句一般用虚拟语气，其虚拟语气的结构为：(should) + 原形动词。如：The teacher advised that we should make good use of every minute here. 老师劝我们要好好地利用在这儿的每一分钟。The Party asked that we should serve the people with our heart and soul. 党要求我们要全心全意地为人民服务。但是，当insist的意思为：坚决认为，坚持说；suggest的意思为：表明，暗含，暗示等时，宾语从句一般不用虚拟语气。如：Tom insisted that he hadn’t stolen the watch. 汤姆坚持说他没有偷那块手表。His smile suggested that he had succeeded in this exam. 他的微笑表明他在考试中成功了。2. believe, expect, suspect, think, imagine 等动词的否定句或疑问句中的宾语从句常用虚拟语气。其虚拟语气的结构为：should + 原形动词。如：Can you believe that he should kill a tiger? 你能相信他竟杀死了一只老虎？Can you imagine that he should take the first place in the long jump contest? &你能想象得到他在跳远比赛中竟获得了第一名？3. 英语中，wish 之后的宾语从句，表示一种没有实现或根本不可能实现的愿望，常用虚拟语气。其虚拟语气的结构为：表示所发生的时间 & 虚拟语气结构 & 发生在主句动作之前 & (1)had + 过去分词；(2)would / could / might / should + have + 过去分词 & 与主句动作同时发生 & 过去时(be 用were ) & 发生在主句动作之后 & would / could / might / should + 原形动词 & 例如：I wish I learnt English well. 我希望我已学好了英语。I wish I had been there with them last week. 我希望上周跟他们一起在那儿。He wishes we could go and play games with him. 他希望我们能去跟他做游戏。4. 英语中，would rather, had rather, would sooner等之后的宾语从句常表示与客观事实不相符的一种愿望，故使用虚拟语气。其虚拟语气的结构为：表示所发生的时间 & 虚拟语气结构 & 过去 & had + 过去分词； & 现在 & 过去时(be 用were ) & 将来 & 过去时(be 用were ) & 例如：I’d rather you had seen the film yesterday. 我倒想你昨天看过了这场电影。I’d rather you were here now. 我倒想你现在在这儿。We’d rather you went here tomorrow. 我么倒想你明天去那儿。四、主语从句中的虚拟语气在表达惊异、惋惜、遗憾、理应如此等意义的主语从句中常使用虚拟语气，其虚拟语其的结构为： should + 动词原形，主句中的谓语动词形式不限。句型：(1) It is admirable / dreadful / extraordinary / odd / remarkable / sad / advisable / annoying / disappointing / surprising / upsetting / frightening / better / best / curious / desirable / important / strange / peculiar / proper / necessary / natural …that…(2) It is a pity / a shame / no wonder…. that…(3) It is suggested / requested / desired / proposed /…. that …(4) It worries me that…如：It is important that we should do well in our lessons first. 我们先把功课学好很重要。It is strange that he should not come. 很奇怪，他竟没有来。It is a pity that we should not meet last night. 真遗憾我们昨天晚上没有见过面。It worries me that we should be blamed for that. 我们竟要受责备真让人烦恼。五、表语从句及同位语从句中虚拟语气英语中，表示请求、要求、命令、建议等名词advice, desire, decision, idea, instruction, order, plan, proposal, recommendation, request, requirement, suggestion, wish充当句子的主语而后面接表语从句或它们后面接同位语时，表语从表面上看几屗及同位语从句都须用虚拟语气。其虚拟语气的结构为：(should) &+ 动词原形。如：We followed his advice that we should ask our teacher for help. 我们接受了他的建议：我们应该请求老师的帮助。He told us his idea that he should go to university. 他告诉了我们他的想法：他想上大学。His suggestion is that we should do our work more carefully. 他的建议就是我们的工作要更细心些。Their plan is that they should build a new factory in their hometown. 他们的计划就是在家乡建一座新工厂。六、定语从句中的虚拟语气英语中，表示：“早该做某事了”时，定语从句中的谓语动词须用虚拟语气，其虚拟语气的结构为：It is (high / about) time that + 主语+ 动词的过去式/ should + 动词原形。如：It is time that I went to pick up my daughter at school. 我该去学校接我的女儿了。It is high time you should go to work. 你早该上班了。七、简单句中的虚拟语气1. 说话时，为了表示客气、谦虚、委婉而有礼貌，言语常使用虚拟语气。其虚拟语气的结构形式常为：would / could / might / should + 原形动词。如：Would you mind my shutting the door? &我把门关起来你介意吗？You should always learn this lesson by heart. 你要把这个教训牢记于心。I should agree with you. 我应该同意你的观点。2. 表示“祝愿”时，常用“may + 主语 + 动词原形 + 其他”。如：May you have a good journey! 祝你一路顺风。May your youth last for ever! 祝你青春永驻。3. 表示强烈的“愿望”、“祝愿”时，常用动词原形。如：Long live the Communist Party of China. 中|国|共|产|党|万|岁。God bless us. 上帝保佑。4. 习惯表达中常用的虚拟语气。(1) 提出请求或邀请。如：Would you like to have a talk with us this evening? 今天晚上来跟我们聊天好吗？Could I use your bike now? 我可以用一下你的单车吗？(2) 陈述自己的观点或看法。如：I should glad to meet you. 见到你我会很高兴。I would try my best to help you. 我会尽力帮助你。(3) 提出劝告或建议。如：You’d better ask your father first. 你最好先问一问你的父亲。You should make a full investigation of it first. 你应该先全面调查一番。(4) 提出问题。如：Do you think he could get here on time? 你认为他能按时来吗？Do you expect he would tell us the truth? 你期望他会告诉我们真相吗？(5) 表示对过去情况的责备时，常用虚拟语气。其虚拟语气的结构为：“情态动词 + have + 过去分词”。如：You should have got here earlier. 你应该早就到这里了。You should have returned it to him. 你应该把他还给他了。
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1. (表示条件)如果 He will come if you invite him. 如果你请他,他会来的。 2. (表示虚拟)假如,要是 If I were you, I would never do that. 如果我是你,我决不做那件事。 3. (表示让步)即使 We'll go even if it rains. 即使下雨我们也要去。 4. 是否 I wonder if she is ill. 不知她是否病了。 5. (表示因果关系)每一次...的时候(总是会) If I feel any doubt, I inquire. 我一感到有疑问就随时询问。 n. 1. 条件;设想[C] There are too many ifs in his offer. 他的提议中条件太多了。
if you did/were...,I would do...
if you had done... , I would have done...
if it should/would do...,I would do...
1. (表示条件)如果 ,主句用，if用现在时表示将来 He will come if you invite him. 如果你请他,他会来的。 2. (表示虚拟)假如,要是 1）时态：可以表示过去，现在和将来的情况。它的基点是时态。 a. 同现在事实相反的假设。
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
should(would) have+
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+
would + 动词原形 should+ 动词原形 If you succeeded, everything would be all right. If you should succeed, everything would be all right. If you were to succeed, everything would be all right
if是英语中出现频率很高的，并且它的用法也很多。学生感到很难掌握，为了让同学们更多更好地了解其用法及其。现结合教学中遇到的情况，予以归纳，以供参考。
一、if作为连词，引导，它表示的意思是“假如”“如果”等。在中如果主句用将
来时，则if引导的用。例如：
1. If it doesn’t rain, we will go to the park next Sunday. 如果天不下雨，下期天我们将去公园。
2. If you ask him，he will help you．如果你求他，他将会帮助你。
二、if还可以引导。这时if当作“即使是”，“虽说”解。例如：
1. If she’s poor，at least she’s honest． 虽说她很穷，但至少她还是诚实的。
2. If I am wrong，you are wrong， too． 即使说我错了，那么你也不对。
3. I’ll do it, even if it takes me all the afternoon． 虽然会花费我一下午的时间，我还是要做这事。
三、if作为连词还可以引导。引导宾语从句时和whether意思相同。例如：
1. Lily asked if ／ whether she liked it. 问她是否喜欢它。
2. She asked if ／ whether they had a cotton one． 她问是否他们有一件棉织的。
四、if引导，当if做“当”或“无论何时”解而不含有条件之义时，if中的时态与主句中的时态相同。例如：
1. If youmix yellow and blue，you get green．你将黄色与蓝，便会得到绿色。
2. If she wants the servant，she rings the bell．每当她需要仆人时，她便按铃。
五、if后接否定动词，用于中，表示沮丧、等。例如：
I. Well，if I haven’t left my false teeth at home!真倒霉，我把丢在家里了!
2. And if he didn’t try to knock me down!(What do you think he did!He tried knock me down!)你猜他想做什么?他想把我撞倒!
六、用于中，if从句中用过去式，表示不可能实现，大概不会实现或提出作为考虑的假定条件。例如：
1. If you were a bird, you could fly.假使你是只鸟，你便会飞了。
2. If I asked him(if I were to ask him) for a loan，would he agree?如果我向他，他会答应吗?
另外，if从句中用过去完成式，表示过去未实现的条件(例如由于不可能实现或某人之未能实行)。例如：
1. If they had startedearlier，they would have arrivedin time．要是他们早些动身，他们便可及时到达了。
2. If they had not started when they did，they would not be here now．如果他们那时不动身，现在他们就不会在此地了。
第三，在文学体栽中，if有时可省略，然后将主语与所用的(尤其是were，had，should)倒置。例如：
1. Should it (=if it should)be necessary，I will go. 倘若有必要，我会去的。
2. Were I(=if I were) in your place，I would do the same ． 如果我处于你的位置，我也会这样干的。
3. Had I(=if I had)known earlier，I would come．如果我早一点知道，我就会来。
七、if与其它一些的连用。
首先，as与if连用，它的意思是：“仿佛、好像”同样引导从句。例如：
1. It isn’t as if we are rich．(We are not rich．)我们不像富有的样子。(即我们不富有)
2. It isn’t as if he doesn’t know the ruler．(i．e．He does know the rulers．)他不像不懂规则的样子。(即他懂得规则)
另外as if还可以引导感叹句。例如：
As if I would allow it!(i．e．I would certainly not allow it!)好像我会答应似的!(我才不会答应哩!)
其次, if与only连用。常表示愿望或一个未实现的条件，尤其用于感叹句中。例如：
1. If only he arrives in time!他若能及时到达就好了!
2. If only she would marry me!但愿她能嫁给我！
3. If only she had known about it!（But she didn’t know.） 她那时要是知道（但她不知道）这事就好了!
if是英语中出现频率很高的连词，并且它的用法也很多。学生感到很难掌握，为了让同学们更多更好地了解其用法及其语法功能。现结合教学中遇到的情况，予以归纳，以供参考。
一、if作为连词，引导条件状语从句，它表示的意思是“假如”“如果”等。在复合句中如果主句用将
来时，则if引导的状语从句用一般现在时。例如：
1. If it doesn’t rain, we will go to the park next Sunday. 如果天不下雨，下周星期天我们将去公园。
2. If you ask him，he will help you．如果你求他，他将会帮助你。
二、if还可以引导让步状语从句。这时if当作“即使是”，“虽说”解。例如：
1. If she’s poor，at least she’s honest． 虽说她很穷，但至少她还是诚实的。
2. If I am wrong，you are wrong， too． 即使说我错了，那么你也不对。
3. I’ll do it, even if it takes me all the afternoon． 虽然会花费我一下午的时间，我还是要做这事。
三、if作为连词还可以引导宾语从句。引导宾语从句时和whether意思相同。例如：
1. Lily asked if ／ whether she liked it. 莉莉问她是否喜欢它。
2. She asked if ／ whether they had a cotton one． 她问是否他们有一件棉织的。
四、if引导时间状语从句，当if做“当”或“无论何时”解而不含有条件之义时，if从句中的时态与主句中的时态相同。例如：
1. If youmix yellow and blue，you get green．你将黄色与蓝色混合，便会得到绿色。
2. If she wants the servant，she rings the bell．每当她需要仆人时，她便按铃。
五、if后接否定动词，用于感叹句中，表示沮丧、惊奇等。例如：
I. Well，if I haven’t left my false teeth at home!真倒霉，我把假牙丢在家里了!
2. And if he didn’t try to knock me down!(What do you think he did!He tried knock me down!)你猜他想做什么?他想把我撞倒!
六、用于虚拟语气中，if从句中用过去式，表示不可能实现，大概不会实现或提出作为考虑的假定条件。例如：
1. If you were a bird, you could fly.假使你是只鸟，你便会飞了。
2. If I asked him(if I were to ask him) for a loan，would he agree?如果我向他借贷，他会答应吗?
另外，if从句中用过去完成式，表示过去未实现的条件(例如由于不可能实现或某人之未能实行)。例如：
1. If they had startedearlier，they would have arrivedin time．要是他们早些动身，他们便可及时到达了。
2. If they had not started when they did，they would not be here now．如果他们那时不动身，现在他们就不会在此地了。
第三，在文学体栽中，if有时可省略，然后将主语与所用的限定动词(尤其是were，had，should)倒置。例如：
1. Should it (=if it should)be necessary，I will go. 倘若有必要，我会去的。
2. Were I(=if I were) in your place，I would do the same ． 如果我处于你的位置，我也会这样干的。
3. Had I(=if I had)known earlier，I would come．如果我早一点知道，我就会来。
七、if与其它一些介词的连用。
首先，as与if连用，它的意思是：“仿佛、好像”同样引导从句。例如：
1. It isn’t as if we are rich．(We are not rich．)我们不像富有的样子。(即我们不富有)
2. It isn’t as if he doesn’t know the ruler．(i．e．He does know the rulers．)他不像不懂规则的样子。(即他懂得规则)
另外as if还可以引导感叹句。例如：
As if I would allow it!(i．e．I would certainly not allow it!)好像我会答应似的!(我才不会答应哩!)
其次, if与only连用。常表示愿望或一个未实现的条件，尤其用于感叹句中。例如：
1. If only he arrives in time!他若能及时到达就好了!
2. If only she would marry me!但愿她能嫁给我！
3. If only she had known about it!（But she didn’t know.） 她那时要是知道（但她不知道）这事就好了!
O(∩_∩)O~
这些绝对够你用了啦
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外语领域专家
