从A、B、C、D四个选项中,选出可以填入空白处的最佳答案。
21.___book I read yesterday is so interesting that I want to read it___ second time.
A. x; the                                                   B. The ;x
C. The; a                                                   D. A; the
22.---What are you doing ,Jack?
 ---I’m making a model car. I _______ it in the science class at 10 o’clock tomorrow morning.
A. will be showing                                     B. would show
C. have shown                                           D. show