It's very nice of you to write to me,为什么用of

It's very nice of you to write to me,为什么用of It is very nice ___ you to write to me.A.of B.on C.for it is very -------of you to write to me.A：nice B；better C：we It is very nice of you to help me 为什么要用of it's very nice for/of/to you to help me of/with/for my Engli It's very nice of you to help me with my English.中为什么填to hel Susan:Rosemary,It’s very nice of you to invite me to dinner It very nice ( )you to ( ) me about it怎么选 A for ;tell B of;s It's very kind of you to help me 为什么用of It's very nice ___pictures for me.ofA.of you to draw B.for y It's very nice of you to meet me at the airport.(改为同义句） It's very nice of you to get me two tickets ____ the World C