Unit2SectionⅡ语法：虚拟语气（II）-河北安平中学高中英语人教新课标选修六学案

SectionⅡ语法：虚拟语气(II)

1.主语从句中的虚拟语气

(1)在“ It is important( necessary,strange,natural,a pity等)+that从句”句型中，从句的谓语动词常用“ should+动词原形”，should可以省略。

It is necessary that I(should) return it right now.

我有必要马上把它还回去。

It is important that this task( should) not fail.

重要的是这项任务不能失败。

It's a pity that he should have failed in the exam.

他考试竟没有及格，真是遗憾。

注意：这种句型中的主语从句有时也可不用虚拟语气而用陈述语气。

It's strange that we haven't heard from him.

奇怪，我们一直没有收到他的来信。

It's a pity that you can't stay longer.

你不能再多停留些时间，真是遗憾。

(2)在“ It is ordered( deci ded, suggested, requested, required，proposed等)+that从句”句型中，从句谓语动词用“ should+动词原形”，should可以省略。

It is required that the students( should) learn a foreign language.

学生们被要求学一门外语。

It was decided that the school should buy new software.

学校要购买新软件，这已经决定下来了。

2.表语从句和同位语从句的虚拟语气

在表示建议、命令、要求、愿望等名词后面的表语从句和同位语从句中谓语动词用“( should+)动词原形”。这类名词有：advice, suggestion, order, demand, proposal, request, desire等。

He made the demand that we should go at once.

=His demand was t hat we should go at once.

他要求我们马上去。

3.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所表示的时间作出相应的调整。

If you had listened to me, you wouldn’t be in such trouble now.

如果你听了我的话，你现在也不会有这样的麻烦了。

(从句说明过去，主句说明现在)

If I were you, I would have taken his advice.

如果我是你，我就会接受他的忠告了。(从句说明现在，主句说明过去)

注意：混合虚拟语气句还有一种情况就是事实和虚拟假设的混合，这样的句子不仅仅是时间的不同，更重要的是事实和假设的混合。

I would have gone to visit him in the hospital had it been at all possible, but I was fully occupied the whole of last week.

如果有可能我就去医院看他了，但是我整个上周都很忙。

(前半部分表示假设，而后半部分是陈述事实）

4.含蓄条件句

有时假设的条件不通过条件从句表达出来，而是暗含在单词、短语或上下文中，这时需要根据句中所表述的意义以及某些特定的信息词来判断此时需要采用的形式。常用词或短语有: without,but for,or,otherwise等。

Without your help(= Had it not been for your help), I couldn't have achieved all this.

要不是有你帮助，我是不会取得这些成绩的。

But for his pension, he would starve.

要不是有养老金，他都要饿死了。

Five minutes earlier and you could have met her at the station.

早来五分钟的话，你就能在车站见到她了。

5.as if/as though从句以及if only后的句子常用虚拟语气

as if/ as though/

if only 时间谓语动词的虚拟形式

与过去事实相反had+过去分词

与现在事实相反一般过去时（be动词用were）与将来事实相反would/could/might+动词原形

He treats the little girl as if she were his own daughter.