表语从句：

    在复合句中担任表语的从句叫表语从句。表语从句放在连系动词之后，其语序正装。

    一、引导表语从句的连接词：

1、that引导陈述句，只起连接作用，其本身无意义，在口语或非正式英语中可以省。例如：

The fact is that Bill has known it.事实是比尔已经知道了这件事。

But the fact remains that we are behind the other classes.事实是我们任然落在别人的后面。

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

My suggestion is that he (should) turn the land into rice field.我的建议是他应该把这块土地改造成稻田。

2、whether引导一般问句、选择问句和反义问句，意思是“是否”，语序正装。例如：

The question is whether we will go for an outing tomorrow.问题是明天我们是否去郊游。
My question is whether he left（or not）。 我的问题是他是否离开了。

The question is whether we can make good preparation in such a short time.问题是我们是否能在这么短的时间内做好准备。

3、as, as if/though,意思是“似乎、好像”。

She looks as if she were the mother of the orphons. 她就好像是那些孤儿的妈妈一样。

Things are not as they seemed to be.情况并不是看上去的那个样子。

He looked just as if he had looked ten years before.  他看起来还与十年前一样。

It sounds as if someone is knocking at the door. 听起来好像有人在敲门。

He looks as if he's tired. 他好像累了。

4、because, 意思是“因为”

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

    That’s because he was ill.那是因为他当时生病了。

It was because he didn't pass the exam.那是因为他没有通过考试。

5、who, whom, which, whose, where, when, why, how疑问词引导特殊问句，在从句中担任句子成分。例如：

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

    What we looking into is what caused the accident . 我们正在调查的是造成事故的原因。
    A question worth attention is how we can stop pollution. 一个值得注意的问题是我们如何控制污染。

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

That’s where we differ.这就是我们的分歧所在。

So that’s who he is working for.所以说他就是为这种人卖命的。

September is when children start school.九月是孩子开学的时间。

Good doctor sare what we need更多的书籍是我们需要的。

二、带表语从句的系动词

可接表语从句的连系动词除be外，常见的有：look，seem，sound，appear，remain,等。例如：

    China is no longer what she used to be. 今日的中国不再是过去的中国了。

    The question remains whether they will be able to help us.   问题还是他们能否帮我们。

    At that time，it seemed as if I couldn't think of the right word.  当时，我似乎怎么也想不出一个恰当的字眼来。

三、使用表语从句要注意的几个问题

1、比较：That's because…强调原因；That's why…强调结果。例如：

That's because he didn't understand me.   那是因为他没有理解我。

This is why we can’t get the support of the people这就是我们为什么得不到别人支持的原因。

That's why he got angry with me. 那正是他对我生气的原因。

    名词reason作主语时，表语从句用that而不用because或why引导，例如：.

The reason why I was sad was that he didn't understand me.我难过的原因就是他不理解我。

The reason why he is late for school is that he missed the early bus.他上学迟到的原因就是他误了早班车。

2、what和that在表语从句中的区别

what除了充当引导词外还在从句中长当成分，其意义相当于一个名词加that引导的定语从句（something that…），其强调式whatever=anything that…; that只起连接作用，不充当句子成分。例如：

That was what we wanted to know. 那是他想要知道的

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 seems to be what we should answer for.好像这就是我们要负责人的事。

3、if不能引导表语从句。

4、使用虚拟语气的表语从句

    在表示建议、劝告、命令等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，request,requirement,demand, recommendation, wish,等。

My suggestion is that she （should） start early tomorrow. 我的建议是她明天一早就出发。

参见“名词性从句概述”