20. I can’t find my dictionary now. Tom must have taken it by mistake, ______?

　 A. mustn’t he 　　　　　　　　　　 B. doesn’t he　　　　　　　　　　 C. didn’t he　　　　　　　 D. hasn’t he

19. Many a student ____ going to have themselves ______ in the hospital.

A. is ; to examine　　　　 B. are ; examine　　　 　　　 C. is ; examined D. are ; examining