就是由that引导的从句,可以是宾语从句,主语从句,表语从句,同位语从句和定语从句. that在宾语从句,主语从句,表语从句,同位语从句中没词义,宾语从句中可省略.在定语从句中指代先行词,that在定语从句中做宾语时可以省略...

主语:

That he is still alive is sheer luck.

他还活着全靠运气。

宾语:

John said that he was leaving for London on Wednesday.约翰说他星期三要到伦敦去。

表语:

The fact is that he has not been seen recently.事实是近来谁也没有见过他。

同位语:

The fact that he has not been seen recently disturbs everyone in his office.

近来谁也没有见过他，这一事实令办公室所有的人不安。

形容词宾语:

I am glad that you are satisfied with your job.

你对工作满意我感到很高兴。

除此之外，That-从句作主语通常用it作先行词，而将that-从句置于句末。

eg：

It is quite clear that the whole project is doomed to failure.

很清楚，整个计划注定要失败。

eg：

It's a pity that you should have to leave.

你非走不可真是件憾事。

用it作形式主语的that-从句有以下四种不同的搭配关系：

1、It + be +形容词+ that-从句

It is necessary that…　有必要……

It is important that…　重要的是……

It is obvious that…　很明显……

2、It + be + -ed 分词+ that-从句

It is believed that…　人们相信……

It has been decided that…　已决定……

3、It + be +名词+ that-从句

It is common knowledge that…　 ……是常识

It is a surprise that…　令人惊奇的是……

It is a fact that…　事实是……

4、It +不及物动词+ that-分句

It appears that…　似乎……

It happens that…　碰巧……

It occurred to me that…　我突然想起……。