一、概念
虚拟语气：表示动作或状态不是客观存在的事实，而是说话人的主观愿望、假设或推测等。
如：If I were you,I should study English.如果我是你，我就学英语了。
May you succeed!祝您成功!
二、虚拟语气在条件从句中的用法
条件句有两类，一类是真实条件句，一类是虚拟条件句。
⒈ 真实条件句
如果假设的情况是有可能发生的，就是真实条件句。在这种真实条件句中的谓语用陈述语气。
如：If it doesn't rain tomorrow,we will go to the park.如果明天不下雨，我们就去公园。
⒉ 虚拟条件句
如果假设的情况是过去或现在都不存在的，或将来不大可能发生的，则是虚拟条件句。
技公司软网途点-升9309421f限4341元西学东科广有慧习件a3fa优 如：If he had seen you yesterday,he would have asked you about it.如果他昨天见到你，他会问你这件事的。(事实上他昨天没见到你，因此也未能问你这件事。)
⒊ 错综时间条件句
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，被称为错综时间条件句，动词的形式要根据它表示的时间作出相应的调整。
如：If you had followed my advice just now you would be better now.
If you had studied hard before,you would be a college student now.
⒋ if省略句
在条件句中可以省略if，把were,had,should提到句首，变成倒装句式。
如：If I were at school again,I would study harder.
→Were I at school again,I would study harder.如果我还有上学的机会，我会更加努力学习。
If you had come earlier,you would catch the bus.
→Had you come earlier,you would catch the bus.如果你来得早点，你就能赶上公共汽车。
If it should rain tomorrow we sould not go climbing.
→Should it rain tomorros iwe would not go climbing.如果明天下雨的话，我们就不能登山去了。
⒌ 用介词代替条件状语从句
常用的介词有with,without，but for。
优途点点慧习学学限4341升9309421f费东7393广高公软2138c99e司高技97ad-件a3fa元西有b00cd9980512网科
如：What would you do with a million dollars?(=if you had a nillion dollars)如果你有100万元，你会做什么?
We couldn't have finished the work ahead of time without your help(=if we hadn't got your help)没有你的帮助，我们不可能提前完成这项工作。
Without your help we couldn't have finished the work ahead of time.
=But for your help,…
=If it had not been for your help,…
=Had it not been for you help,…
没有你的帮助，我们不可能提前完成这项工作。
⒍ 含蓄条件句
有时在虚拟语气中并不总是出现if引导的条件句，而是通过其他手段来代替条件句。
如：I was ill that day.Otherwise, would have taken part in the sports meeting.(副词)
He telephoned to inform me of your birthday,or I would have known nothing about it.(连词)
A man who stopped drinking water would be dead in about seven days.(定语从句)
元西高优的学-有b00cd9980512点东7393途点点34d5软2138c99e费网公4afc技97ad限4341慧习学科e1830af9广高b1eb件a3fa升9309421f费司高
I might hawe given you nore help,but I was too busy.(连词)Everything taken into consideration they would have rai sed their output quickly.(独立主格结构)