虚拟语气的用法
用法如下：1、与现在事实相反：若与现在事实相反，条件从句的谓语用过去式(be通常用were)，主句谓语用“should (would, could, might)+动词原形”。2、与过去事实相反：若与过去事实相反，条件从句的谓语用过去完成时(had+过去分词)，主句谓语用“should (would, could, might)+have+过去分词”。3、与将来事实相反：若与将来事实相反，条件从句的谓语用过去式(be通常用were)，主句谓语用“should (would, could, might)+动词原形”。虚拟语气的应用条件：在表示假想的虚假的、与事实相反的或难以实现的情况时用虚拟语气，表示主观愿望或某种强烈情感时，也用虚拟语气。即当一个人说话时欲强调其所说的话是基于自己的主观想法，愿望，假想，猜测，怀疑或建议，而不是根据客观实际，就用虚拟语气。主要是英语语法的一种表达。条件句可分为两类，一类为真实条件句，一类为非真实条件句。非真实条件句表示的是假设或实际可能性不大的甚至完全不可能发生的情况，故采用虚拟语气。
虚拟语气的各种用法
1、与现在事实相反：若与现在事实相反，条件从句的谓语用过去式(be通常用were)，主句谓语用“should (would, could, might)+动词原形”。2、与过去事实相反：若与过去事实相反，条件从句的谓语用过去完成时(had+过去分词)，主句谓语用“should (would, could, might)+have+过去分词”。3、与将来事实相反：若与将来事实相反，条件从句的谓语用过去式(be通常用were)，主句谓语用“should (would, could, might)+动词原形”。扩展资料：虚拟语气的应用条件：在表示假想的虚假的、与事实相反的或难以实现的情况时用虚拟语气，表示主观愿望或某种强烈情感时，也用虚拟语气。即当一个人说话时欲强调其所说的话是基于自己的主观想法，愿望，假想，猜测，怀疑或建议，而不是根据客观实际，就用虚拟语气。主要是英语语法的一种表达。条件句可分为两类，一类为真实条件句，一类为非真实条件句。非真实条件句表示的是假设或实际可能性不大的甚至完全不可能发生的情况，故采用虚拟语气。参考资料来源：百度百科-虚拟语气
英语中虚拟语气的具体语法？
虚拟语气应该是必修3第一、二单元的知识点.
常规下虚拟语气的考查点分两个：
一是名词性从句中should do结构,should可以省略.在名词性从句中,如果出现表示“命令,建议,请求、计划”的词,不管它用于什么名词性从句,都要求使用虚拟语气.如：
He suggested that we (should) finish the task on time.这是宾语从句,suggest是“建议”的意思.又如这词用于表语从句：
His suggestion was that we (should) finish the task on time.
在这种从句中,要注意一点就是：如果从句的主语和谓语动词之间是被动关系,那么就要用(should) be done结构,就和情态动词的被动形式一样.如：
He ordered that the task (should) be finished on time.
二是条件状语从句中的虚拟语气.从句和主句的谓语动词有严格规定,如下：
从句, 主句
和现在相反： did/ were would/could/ should/ might do
和过去相反： had done would/could/ should/ might have doe
和将来相反： did/ were to do/ should do would/could/ should/ might do
如：如果当时你没帮助我们,我们不可能完成这工程.
If you had not helped us then, we couldn't have pleted the project.(与过去相反).
如果我是你的话,我会用另一种方法.
If i were you, I would use another way to do it.(与现在相反),这句中,要注意到我用的是were.尽管主语是单数,虚拟语气中的一般过去式,不能用was.
这些是基本规则,当然还有很多其他的.如：
I wish that.这个结构是个名词性从句中的宾语从句,但是它使用的虚拟语气不与我上面讲到的相同.这个句型中,宾语从句的时态要往过去推前一步.即：如果与现在相反,用一般过去时,如果和过去相反,用过去完成时,如果与将来相反,用过去将来时.
如：I wish that i were a bird.与现在相反
I wish that i hadn't wasted a lot of time before.与过去相反.
要全部讲具体,比较难,建议你系统看一下相关语法书会好些.,2,
英语语法的虚拟语气
虚拟语气
一、考点聚焦
1、虚拟语气用于条件状语从句中
（1）表示与现在事实相反的假设,条件状语从句中的谓语动词用“过去式（be动词的过去式用were）”,而主句中的谓语动词用“would / should/ could / might + 动词原形”.如：
If I were a boy,I would join the army.
If the had time,she should go with you.
（2）表示与过去的事实相反,条件状语从句中的谓语动词用过去完成时,主句中的谓语动词则用“would / should / might / could + have +过去分词”.如：
If he had taken my advice,he would have succeeded in the petition.
（3）表示与将来事实相反,条件状语从句中的谓语动词一般过去时或should(were to) + 动词原形,而主句中的谓语动词则用would / should/
could might + 动词原形.如；
If it were to rain tomorrow,the football match would be put off.
（4）当条件状语从句表示的行为和主句表示的行为所发生的时间不一致时,动词的形式要根据它所表示的时间作相应调整.如：
If they had worked hard,they would be very tired.(从句说的是过去,主句指的是现在)
以下表格是虚拟语气用于条件状语从句中时,主句和从句谓语动词的形式：
条件状语从句 主 句
与过去事实相反 had + 过去分词 should /would/could/might + have + 过去分词
与现在事实相反 一般过去时(be用were) would/should/could/might + 动词原形
与将来事实相反 一般过去时或should(were to) + 动词原形 Would/should/cold/might + 动词原形
有时侯在使用时可省略if,句子则可换成下列形式,即“were / had / should +主语”.如：
Were I a boy,I would join the army.
Had he taken my advice,he would have succeeded.
Were it not for the expense,I would go to Britain.
2、虚拟语气用于名词性从句
（1）虚拟语气在宾语从句中的运用.
①“wish + 宾语从句”表示不能实现的愿望,译为“要是……就好了”等.表示现在不能实现的愿望,从句中的谓语动词用一般过去时；表示将来不能实现的愿望,从句中的谓语动词用“would/could + 动词原形”；表示过去不能实现的愿望,从句中的谓语动词用“had + 过去分词”或“could(should) + have + 过去分词”.如：
I wishit were springall the year round.
I wishI had known the answer.
I wishI could fly like a bird.
②在表示建议、要求、命令等的动词suggest、advise、propose、demand、require、insist request、mand、order等后的宾语从句中,谓语动词用should + 动词原形或是动词原形.如：
She suggested we (should)leave here at once.
The doctor ordered she should be operated.
（2）虚拟语气在同位语从句和表语从句中的运用.
作表示建议、要求、命令等的名词advise、idea、order、demand、plan、proposal、suggestion、request等的表语从句和同位语从句,从句中的谓语动词用“（should） + 动词原形”.如：
His suggestion that we (should)go to Shanghai is wonderful.
My idea is that they (should)pay 100 dollars.
（3）虚拟语气在主语从句中的运用.
在主语从句中,谓语动词的虚拟语气用“should + 动词原形”的结构,表示惊奇、不相信、理应如此等.如：
It is necessary(important,natural,strange,etc.)that we should clean the room every day.
It was a pity (a shame,no wonder,etc.)that you should be so careless.
It will be desired(suggested,decided,ordered,requested,proposed,etc.)that she should finish her homework this afternoon.
注意：这种从句表示的是事实.如果说人对这种事实表现出惊奇的情感,就可用虚拟语气.反之,如果不表示惊奇等情感,that从句也可用陈述句语气.如：
It is pity that you can’t swim.
3、虚拟语气在其他场合的运用
（1）虚拟语气在as if/as though、even if/even though等引导的表语从句或状语从句中,如果从句表示的动作发生在过去,用过去完成时；指现在状况,则用一般过去时；指将来状况则用过去将来时.如：
He did it as if he were an expert.
Even if she were here,she could not solve the problem.
（2）虚拟语气用于定语从句中.
这种从句常用于句型“It is (high)time (that) … ”中,定语从句的谓语动词用一般过去时(be用were)或should + 动词原形,意思是“(现在)该……”.如：
It’s time that I picked up my daughter.
It’s high time we were going.
（3）虚拟语气用在if only引导的感叹句中.如：
If only I were a bird.
If only I had taken his advice.
（4）虚拟语气在一些简单句中的运用.
①情态动词的过去式用于现在时态时,表示说话人谦虚、客气、有礼貌或语气委婉,常出现在日常会话中.如：
It would be better for you not to stay up too late.
Would you be kind enough to close the door?
②用于一些习惯表达法中.如：
Would you like a cup of tea?
I would rather not tell you.
