It was clever of you to answer this question为什么用of而不用for,不是it is adj for sb to do

It was clever of you to answer this question
为什么用of而不用for,不是it is adj for sb to do

it is adj for sb to do sth意思是对某人来说做某事很adj,这个着重修饰后面的sth,而用of则着重修饰sb,意思是某人做某事很adj,可以翻译成汉语,找找语感,再回答.答英语不能死套句型的.

因为clever 是修饰 you的，修饰人的形容词可以用 of 或for
举个例子：
It was kind of you to help me.
It was kind for you to help me.是一个意思