虚拟式
虚拟式，作为专门表达假设意义和其他非事实意义的动词形式，仅是古英语一流下来的残余。主要有两种形式，be-型虚拟式和were-型虚拟式。
Be-型虚拟式：
Be-型虚拟式是以动词原形表示的，即不管主语是什么人称，动词一律用原形，如I go, you go, he go或者I be, you be, he be.如果动词为被动态，则动词be也一律用原形，如I be nt。因此，如果主语是复数，便显示不出虚拟式与陈述式的区别；除了虚拟式be与陈述式am/is/are/was/were有所区别外，其他动词的be-虚拟式只有在单数第三人称主语之后才是有标记的。
Be-型虚拟式的主要用法如下。
1. 用于表示命令、决定、建议等词语之后的that-分句中。Be-型虚拟式的这一用法又有以下三种情况：
a) 用在decide, decree, demand, insist, move(建议), order, prefer, propo, recommend, request, require, suggest, vote等动词之后的that-分句中。例如：
表示遗憾的句子
He ordered that all the books be nt at once.
We propo that somebody neutral take the chair.
She insisted that she go to the south for her holiday.
Congress has decided/voted/decreed that the prent law be maintained.
The doctor insisted that he not eat meat.
b) 用在advisable, appropriate, desirable, esntial, fitting, imperative, important, impossible, necessary, obligatory, proper等形容词之后的that-分句中。例如：
It is esntial that all the facts be examined first.
It is necessary that he come back without delay.
杜甫的诗被称为什么
I thought it advisable that an armed guard stand in readiness.
It was appropriate that this tax be abolished
It is imperative that this mission not fall.甜甜蜜蜜的意思
c) 用在decision, decree, demand, instruction, order, requirement, resolution等名词之后的that-分句中。例如：
The board has given instructions that the agent fly to Boston.
We were faced with the demand that this tae be abolished.
Your advice that she wait till nest week is reasonable.
Their decision was that the school remain clod.
红烧大肠的做法His order that the troops not be nt at once was carried out.
在这一用法中be-型虚拟式能与“should+不定式”交替使用，也能与to-不定式交替使用。例
如：
He ordered that the books be nt at once. = he ordered that books should be nt at once. = he ordered that the books to nt at once.
It is important that she be placed in an appropriate job. = It is important that she should be placed in an appropriate job. = It is important that she to be placed in an appropriate job.
越想越心痛2. 用于由if, though等引导的分句中
Be-型虚拟式能用于由if, though, whatever, lest, so long as等引导的分句中表示推测、让步、防备等含义。例如：
If he be found guilty, John shall have the right of appeal.
If the rumor be true, everything is possible.
Though everyone dert you, I will not.
Whatever be his defen, we cannot tolerate this disloyalty.
Quietly we sat on the river bank lest the fish swim away.
上述用法现在只限于正式书面语体，在非正式语体中通常用动词陈述式或者用should/may+不定式。例如：
If the rumor is true, everything is possible.
He hid himlf in the bush lest he should be en.
Whatever his defen may be, we can’t tolerate this disloyalty.
3. 用于某些公式化语句中
Be-型虚拟式用于某些公式化语句中可表示祝愿、诅咒，静止等含义。例如：
Long live the People’s Republic of China! 中华人民共和国万岁
God bless you! 上帝保佑你
God damn you! 该死的
Heaver forbid! 天理不容
Devil take him! 混蛋
So be it. 但愿如此/就这样吧
Suffice it to say that… 只需说什么就够了
Home is home, be it ever so homely. 再穷也是家好碰
Were-型虚拟式
Were-型虚拟式只有一种形式，即不管主语是什么人称，动词一律用were，如 I were， you were， he were；如果动词为进行体或被动态，其助动词也一律用were，如I were going, you were going, he were going, I were nt, you were nt, he were nt.因此，were-型虚拟式只有出现在单数第三人称主语之后，它才在形式上与陈述式were区别开来。Were-型虚拟式的主要用法如下。
1. 用于某些状语从句中
Were-型虚拟式常用于由if， if only, as if, as though, though引导的条件状语从句和让步状语分句中，表示非真实条件或让步。例如：
If I were you, I should wait till next week.
If it were to rain, the game would be put off.
重的比较级If only I were not so nervous.
He spoke to me as if I ere deaf.
He behaves as though he were better than us.
Though the whole world were against me, I would do what I consider as right.
2. 用于某些名词性分句中
Were-型虚拟式常用于wish, would rather, suppo, imagine之后的that-分句中，表示一种
臆想的情况。
I wish it were spring all the year round.
I’d rather I were not at the site of the accident.
Suppo the earth were flat.
Just imagine everyone were to give up smoking.
上述were-型虚拟式在第一、三人称单数主语之后可为was所代替。例如：
If it was it rain, the game would be put off.
If only I was not so nervous
I wish it was spring all the year round.
I’d rather I wasn’t at the site of the accident.
但是，在if I were you这一分句中，通常倾向于用were不用was。另外在某些倒装结构中只用were，不用was。例如
Were I to do it (= if I were to do it), I should rely on you.
还有，as it were(作so to speak解，即“宛如”“好比”)结构中也只用were。例如
He is my best friend, my cond lf, as it were.
如前所述，虚拟式在现代英语中已经不是一个重要的语法范畴，许多该用虚拟式的地方常为陈述式所代替。以上所述用should be代替be，用was代替were就是一例，甚至还可根据语义意图干脆用现在时形式。例如
关注的英语I wish I were/was there.
