---Mr. Black, I find  ______  difficult to play the piano well.

 ---Oh, I think you just need to practice more  

A. it                   B. it is                          C. this                D. that

I find _______difficult to get to sleep because the man upstairs made much noise.

    A. it             B. this             C. that             D. him

I find ________ difficult to remember everything, though I’m still young.

I find ________ difficult to remember everything, though I’m still young.

–What do you think of the man？

--I find _____ difficult to work with him.

A．him              B．me               C．it                D．that