Question

1到英语题

选择填空：It's important _ the piano well.
A.of him to play B.for him to play
C.of him playing D.for him playing

Answer 1

选B
It is adj of somebody to do something.这里 的形容词和人要构成主系表关系：比如It is very kind of you to do this.你可以理解成You are very kind to do this.
It is adj for somebody to do something.这里的形容词主要是用来修饰主语it 的，与后面的人没有直接关系，你就不成理解成He is improtant to play the piano well.
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Answer 2

B
It's important for sb. to do sth.

Answer 3

选B
it's adj. for sb. to do sth. 是固定句式

Answer 4

选B
固定句式:
it's + adj. + for sb. to do sth.