It is very kind you to help me with my lessons because it is very difficult me to learn t

问题补充：

It is very kind you to help me with my lessons because it is very difficult me to learn them well.

A. of； for

B. of； of

C. for；of

D. for； for

答案：

(答案→)A. of； for

B. of； of

C. for；of

D. for； for

解析：考查句型：It is +形容词+介词+sb to do的用法。形容词为形容人的性格品质的词，应用介词of,形容词为difficult,necessary等词时，应用介词for 。所以选A。