6. 由as if / as though引导

It isn’t as if you were going away for ever. 又不是你离开不回来了。

Now it was as though she had known Millie for years. 现在好像她认识米莉已有好多年了似的。

It is not as though we were poor. 又不是我们家里穷。

5. 由关系代词型what引导

That’s what I want to stress. 这是我想强调的。

That’s what we are here for. 我们来这里就为了这个。

Fame and personal gain is what they’re after. 他们追求的是名利。

He is no longer what he was. 他已经不是以前的他了。

4. 由连接副词引导

The problem is how we can find him. 问题是我们如何找到他。

That was when I was fifteen. 这是我15岁时发生的事。

That’s where I first met her. 那就是我第一次遇见她的地方。

That’s why he didn’t come. 这就是他没有来的缘故。

That’s why I object to the plan. 这就是我反对这个计划的原因。

That’s where you are wrong. 这就是你不对的地方。

3. 由连接代词引导

You are not who I thought you were. 你已不是我过去所想像的人。

The problem is who we can get to replace her. 问题是我们能找到谁去替换她呢。

The question is who (m) we should trust. 问题是我们应当相信谁。

What I want to know is which road we should take. 我想知道的是我们应走哪条路。

2. 由whether引导

The question is whether the film is worth seeing. 问题是这部电影是否值得看。

[注意]whether 可引导表语从句，但与之同义的if却通常不用于引导表语从句。

引导表语从句的词有连词that, whether，连接代词和连接副词，关系代词型what，以及as if, as though, because等连词。

1. 由that引导

The fact is that he doesn’t really try. 事实是他没有做真正的努力。

The trouble is that I have lost his address. 麻烦的是我把他的地址丢了。

My suggestion is that we should tell him. 我的建议是我们应该告诉他。

His sole requirement was (is) that the system work. 他唯一的要求是这个制度能起作用。

My idea is that we should start making preparations right now. 我的意见是我们马上就开始做准备工作。

2. 引导表语从句的引导词有以下几类。

1)wh-疑问词

My question is who left.

我想问的是谁离开了。

What I wonder is when he left.

我想知道他是何时离开的。

That's what he wants.

那是他想要的。

This is where they once lived.

这就是他们曾经住过的地方。

That is why he didn't come here. 这就是他为何没到这儿来的原因。

2)whether

My question is whether he left(or not). 我的问题是他是否离开了。

注：if不能引导表语从句。

3)that

The fact is that he left. 事实是他离开了。

注：引导表语从句的连词that间或可以省略。

The truth is(that)I didn't go there. 事实是我没去那儿。

4)because，as，as if，as though

It's just because he doesn't know her. 这是仅仅因为他不认识她。

Things are not always as they seem to be. 事物并不总是如其表象。

He looks as if he's tired. 他好像累了。

1. 连系动词be，appear，seem，look等之后可以跟表语从句。

It was because he didn't pass the exam.

那是因为他没有通过考试。

It seems(that)he was late for the train.

看来他没搭上火车。

It appears that she was wrong.

看来她错了。

It seems to me that we should answer for this.

在我看来，我们似乎应该对此事负责。

It appears to her that he wants to teach us all he has.

在她看来，他似乎要把他所会的都教给我们。

6. 使用虚拟语气的表语从句

在表示建议、劝告、命令含义的名词后的表语从句，谓语动词需用"should+动词原形" 表示，should可省略。常见的词有：advice, suggestion, order, proposal, plan, idea等。　

My suggestion is that we (should) start early tomorrow.

我的建议是我们明天一早就出发。

5. 从属连词that。如：

The trouble is that I have lost his address.　

麻烦是我把他的地址丢了。