第1个回答 2022-07-10
一.定义：在复合句中起主语作用从句
二.结构：关联词➕主语从句剩余部分
三.关联词：
1.从属连词：that, whether
2.连接代词：who, what, which, wh-ever
3.连接副词：when, where, how, why, wh-ever
※注意：主语从句放在句首时，整个句子会显得笨重，为了使句子结构平衡，优美，常把主语从句移到后边，前边用引导词"it"做形式主语。
四.it 作形式主语的运用
1.It➕is/was➕名词（名词词组）➕主语从句
It's a fact …
It's a pity …
It's a shame …
It's an honour …
It's a question … 等等
E.g.
It’s a pity that you missed the exciting football match.
It remains a question whether he will come or not.
2.It➕is/was➕形容词➕主语从句
It's natural …
It's obvious…
It's fortunate …
It's possible…
It's unlikely…
3.It➕is/was➕不及物动词（vt.）➕主语从句
It's seems…
It's happened…
It's appears…
It's possible…
It's turns out…
4.It➕is/was➕过去分词➕主语从句
It's known…
It's said…
It's reported…
It's decided…
It's announced…
5.其他形式
It doesn't matter…是无关紧要的
It makes no difderence…毫无区别
It is of little consquence that…无关紧要
It suddenly struck me（occurred me）that…
我突然想到…