这些不定式在句子中充当什么成分啊?

题目

这些不定式在句子中充当什么成分啊?
I find it hard to improve listening.为什么listening是宾语啊?不定式在这里作什么成分的?
I was told to drive the car carefully.为什么carefully是状语啊?不定式在这里作什么成分的?
还有好多象这样的句子啊:she likes to play the piano.
It is important for us to look into the world.那Important在这作什么成分的?for us呢?还有to look...

答案

it hard to improve listening 是省略句,做 find 的宾语.to improve listening 不定式是省略句的实际主语,it 是省略句的形式主语.整个句子还原是：I find (that) it (is) hard to improve listening.省略句主语还原是：I find (that) to improve listening (is) hard.
to play the piano 是 likes 的宾语.
important 做表语.for us 行为人（主语）.to look.是整个句子的实际主语,it 是形式主语.