新概念英语
虚拟语气是谓语动词的一种形式，用于表示所说的话不是事实(甚至与事实相反)，而是一种不可能实现或者实现的可能性较小的主观愿望、建议或假设。以下是根据高考中虚拟语气的常见考点，对其用法进行的小结。
一、虚拟语气在状语从句中的应用
1. 虚拟语气在if引导的非真实条件句中的应用
If引导的非真实条件句的谓语动词应根据时间的不同而与主句谓语动词保持形式上的呼应，其谓语动词形式的对应情况如下表所示：
例如：If it hadn’t been for your wise decision, we wouldn’t have achieved so much in
our work.
If I were you, I would give up the plan.
If it were to (should ) be sunny tomorrow, they could go out for a picnic.
注意：①当非真实条件句中含有had, should或were时，可以省略if并采用倒装语序。
例如：Hadn’t it been for your wise decision, we wouldn’t have achieved so much in our work..
Were I you, I would give up the plan.
Should it be sunny tomorrow, they could go out for a picnic.
②当虚拟条件句与主句的时间不一致时，应根据各自的时间采用上表所对应的谓语动词形式。
例如：If you hadn’t stayed up too late last night, you wouldn’t feel so sleepy now.
If I had gone to study at the normal university, I would be a teacher now.
③if only引导的虚拟条件句或表示主观愿望的感叹句的谓语动词的结构也参照表I所示。
例如：If only I had enough money, I could buy a big house.
If only you had accepted my advice, everything would have gone better.
If only I had got up a little earlier!
If only I went to Britain for further education next year!
2.as if, as though引导的方式状语从句用一般过去时表示现在的情况，用过去完成时表示过去的情况，用would/could+do表示将来的情况。
例如：Lily speaks as if she were a Chinese.
They talked so much as if they hadn’t seen each other for more than one hundred years.
注意：如果as if, as though引导的从句所叙述的内容接近事实或者实现的可能性较大，则不用虚拟语气。
例如：There are so many dark clouds in the sky as if it is going to rain heavily.
3. lest, in case, for fear that引导的目的状语从句一般用(should)+do的虚拟
形式。
例如：Take an unbrella with you in case/lest it (should ) rain.
He put on a heavy coat for fear that he (should ) catch a cold.
二、虚拟语气在名词性从句中的应用
1.表示要求、命令、建议、愿望等意义的动词如suggest, insist, order, command, require, demand, request, advise以及它们的名词形式所接的名词性从句一般要用(should)+do的谓语动词形式。
例如：Mr.Brown suggested that the plan (should be) kept secret.
It was suggested that the plan (should) be kept secret.
Mr Brown put forward the suggestion that the plan (should) be kept secret.
Mr Brown’s suggestion is that the plan ( should) be kept scret
It is advised that the tour leader (should) inform the tourists immediately of any changes in the plans.
The situation required that China (should) open its door to the outside world.
His parents insisted that he ( should ) go to the most well-known university instead of a common one.
注意：① 当suggest表示“暗示”,“表明”，insist表示“坚持认为”时，它们所接的宾语从句不
用虚拟语气。
例如：The expression on her face suggested that she was satisfied with the results.
He insists that the mirror wan’t broken by him.
② 在“It is strange/important/necessary/a pity+that从句”的结构中，that从句常用(should) +do或should have done 的虚拟形式。
例如：It is necessary that every member of the group (should) attend the meeting on time.
It is strange that she should have done such a foolish thing.
③ wish 后接的宾语从句表示现在的愿望时用一般过去时(be 用were),表示过去的愿望时用过去完成时，表示将来的愿望时用could/would+do的结构。
例如：I wish I had enough money to buy a car of my own.
She wished she hadn’t missed the film last night.
We wish we could see each other again quite soon.
④ would rather后的宾语从句用一般过去时表示现在或将来的愿望，用过去完成时表示过去的愿望。
例如：I would rather you came to see me tomorrow.
I would rather I hadn’t attended the party last night.
I would rather he weren’t here now.
三、虚拟语气在定语从句中的应用
在“It is (about/high) time+that从句”的结构中，that引导的定语从句的谓语动
词用should+do的形式，且should不可以省略;或者用一般过去时(be用were)。
例如：It’s (about) time you should go to bed.
It’s (high) time you returned my motorbike.
四、虚拟语气在含有含蓄虚拟条件的句子中的应用
有些句子虽然不含虚拟条件句，但含有以介词(短语)with, without,but for
等，副词or, otherwise或分词短语表示的含蓄的虚拟条件，此时句子应该根据含
蓄虚拟条件所指的时间采用相应的虚拟形式。
例如：Without air and water, there would be no living things on the earth.
But for(Without)your help, I couldn’t have made such great progress.
You’d better put everything where they were; otherwise, your mother would be
angry with you.
Given more time and money, they could have done the work better.
