21. ______ variety of foreign guests were invited to the meeting, and _______total number was over twenty.

A. A, a             B. The, the         C. The, a           D.A, the

22. ----Oh, doctor, I’ve a sharp pain here. I think I am dying.

   ----______ . Let me examine you.

A. Is that this place?               B. Take it easy.   

C. Really?                       D. It’s just OK