1)由从属连词that引导的从句叫做名词性that-从句。 That只起连接主句和从句的作用,在从句中不担任任何成分,本身也没有词义。名词性that-从句在句中能充当主 语、宾语、表语、同位语和形容词宾语,例如:
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。
2)That-从句作主语通常用it作先行词,而将that-从句置于句末,例如:
It is quite clear that the whole project is doomed to failure. 很清楚,整个计划注定要失败。
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:
a. 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……
b. It + be + -ed 分词+ that-从句
It is believed that… 人们相信……
It is known to all that… 从所周知……
It has been decided that… 已决定……
c. 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……
d. 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……