20. The traffic rule says young children under the age of four and ____ less than 40 pounds must be in a child safety seat.

　 A. being weighed　　 B. to weigh　　 　　　　 C. weighed　　　 　　 D. weighing

19. Joining the firm as a clerk, he got rapid promotion, and　　　　 as a manager.

A. ended up　　　 　　 B. dropped out　　　 　　　 C. came back　　 　　　　　　 D. started off

18. The living room is clean and tidy, with a dining table already ______ for a meal to be cooked.

　 　 A. laid　　　　 　　　　　　 B. laying　　　 　　　　　 C. to lay　　　 　　　　　　 D. being laid

17. I have told you the truth. 　　　　　I keep repeating it?

　　　 A. Must　　　　　　　　 　　　 B. Can　　　　　　　　　 　　　 C. May　　　　　　　　 　　　 D. Will