关于不定式语法的问题heissaidtowriteabookoneducationitissaidthathewillwriteabookoneducation为什么第二句要用IT作主语哦,itisdifficulttofinishtheworkwithinaday.ifinditdifficulttoworkwithaday.第二

Question

关于不定式语法的问题
he is said to write a book on education
it is said that he will write a book on education
为什么第二句要用IT作主语哦,
it is difficult to finish the work within a day.
i find it difficult to work with a day.
第二句能不能改成i find to work with a day difficult?
这得这样有点不通,呵.变成IS DIFFICULT呢?
第一句不定式是主语,DIFFICULT是形容词,第二句不定式是宾语,
DIFFICULT是补语,我能不能这样理解,在名词后面的是补语或同位语?

Answer 1

一、不定式主语补足语转换为that主语从句
he is said to write a book on education
it is said that he will write a book on education
这是不定式用作主语补足语改为主语从句（从句后置,其位置由形式主语取代）的同义句转换,
即：某人 + be + 过去分词 + 不定式(主语补足语)
—— 形式主语it + be + 过去分词 + that主语从句
下列所举都属于这种情况：
据说：one is said to do sth —— it is said + that主语从句,
据报道 one is reported to do sth —— it is reported + that主语从句
据通知：one is informed to do sth —— it is informed + that主语从句
另外还有一种类似转换,但谓语动词事主动语态而不是被动语态 .
似乎：one seems to do sth —— it seems + that主语从句
碰巧：one happened to do sth —— it happened + that主语从句
二、it 用作形式主语和形式宾语
形式主语：it is difficult to finish the work within a day.
形式宾语：I find it difficult to work with a day.
注意：能够用it作形式宾语的动词是有限的,仅包括 feel觉得,find发现,think认为,suppose推测,imagine猜想,expect认为,make使得等几个,不可乱用.另外这类情况只能用形式宾语,不可it 后再加is,把后面变成that从句.