— Is there anything you want to know?

— I just wonder ____ that makes Jim so excited.

I just wonder _____ that makes him so excited.

  A. why it is    B. what it is     C. why is it        D.what is it

I just wonder ________ that makes him so excited.

A．why it does? B．what he does

C．how it is? D．what it is

What a woman! I just wonder how she managed to keep smiling after all that she had ________.

 —I just wonder        that made Mark Twain so famous a writer.

—Of course his early experiences.

A. it was what               B. what he did                     C. how he did               D. what it was