英语语法之虚拟语气.doc

虚拟语气（The Subjunctive Mood） 定义： 虚拟语气表示说话人所说的话不是真实的，而是一种假设，愿望，怀疑或是推测。 虚拟语气主要用于条件从句， 让步从句和名词性从句。1. If 引导的条件从句。条件从句 从句主句表示现在的情况If I (you, he/she, we, they)+动词过去式Should/would/could/might+动词原型表示过去的情况If I (you, he/she, we, they)+had+动词过去分词Should/would/could/might+动词过去分词表示将来的情况If I (you, he/she, we, they)+were to +动词原形/动词的一般过去时/should+动词原形Should/would/could/might+动词原型注：虚拟语气中be要用were.例句：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/表示现在的情况）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/现在）3. If I had got there earlier, I should/could have met her.如果我早到那了，我就会见到她。（事实：去晚了，没见到她/表示过去的情况）4. If he had taken my advice, he would not have made such a mistake.如果他听了我的劝告的话，就不会犯这样的错误了。（事实：没听我的话/过去）5. If he should come here tomorrow, I would talk to him. 如果他明天来这儿的话，我就跟他谈谈。（事实：来的可能性很小）6. 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）7. If she were to be here 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。2. 虚拟语气中的倒装。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，即把were, should, had等词置于句首，这种多用于书面语。Were Should +主语+其它HadIf I were you, I would go there. Were I you, I would go there.If she should come earlier this Sunday, she would come to see you. Should she come earlier this Sunday, she would come to see you.Had he learnt about computers, we would have hired him to work here.如果他懂些电脑知识的话，我们已经聘用他来这里工作了。3. 含蓄条件句(1). 条件暗示短语：(without, but for, but, otherwise)We didnt 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。（暗含条件是otherwise） Without your help, we wouldnt have achieved so much. 没有你的帮助，我们不可能取得这么大的成绩。（暗含条件是介词短语without your help） But for your help, I would not have succeeded in the experiment. 如果没有你的帮助，我的实验就不会成功。（暗含条件是but for your help） It would cause great trouble not to lubricate the bearing immediately. 不立即润滑轴承就会引起很大的故障。 （暗含条件是not to lubricate the bearing immediately） （2） 条件暗含在上下文：I would not have done it that way.我是不会那么做的。（可能暗含if I were you）I was busy that day. Otherwise I would have come to help you.我那天很忙，否则我会来帮你的。(可能暗含if I hadnt been so busy)You might come to join us in the discussion.你可以参加我们的讨论。（可能暗含if you had wanted to）I would have bought the DVD player.我是会买下那台影碟机的。（可能暗含if I had the money）4. 错综条件句有时，虚拟条件句中，结果主语和条件从句的谓语动作若不是同事发生时，虚拟语气的形式应做相应的调整。这种条件句叫错综条件句。（1） 从句的动作与过去的事实相反，而主句的动作与现在或现在正在发生的事实不符。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。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.如果他认识她的话， 他肯定会去问候她了。5. Wish 引导的宾语从句a、表示与现在事实相反的愿望，谓语动词用过去式 eg. I wish I had your brains. 我希望我有你那样的头脑。(事实：我根本比不上你) b、表示与过去事实相反的愿望，谓语动词：had+done eg: I wish I had known the truth of the matter. 我希望我那时就知道这件事情的真相。（事实：那时还不知道） c、表示将来难以实现的愿望 谓语动词：should/would（情态动词） + 动词原形 eg. I wish I should have a chance again. 我希望我还能有一次这样的机会。（事实：很难再有这样的机会了） (注：if only引导的感叹句和as if/as though引导的状语从句也有相同用法）6. 目的状语从句1、在for fear that,in case,lest引导的从句中，若用虚拟语气时，从句谓语为：should + do。并且 should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. 他早早的就出发了以防迟到。 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 / could / may / might / will / would / should + do。 He goes closer to the speaker so that he can hear him clearer. 他走近说话的人以便能听得更清楚。 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字。7. 其他用虚拟语气的词一个坚持，两个命令，三个建议，四个要求，后面的冰雨从句中谓语通常用should+动词原形（should可省略）表示愿望建议，命令，请求等。She suggested we (should) leave early.The teacher insisted that the students (should) have a rest.8. If only 要是就好了。（1） 与现在相反 用一般过去时 If only I were you. 要是我是你就好了。（2） 与过去相反 用过去完成时（had+过去分词） If only you had come yesterday.要是你昨天来了就好了。（3） 与将来相反 用would+动词原形If only the rain