51. The Browns _____ dinner when the light suddenly went out(熄灭)

　A. had　　　 B. have had　　 C. was having　　 D. were having

50. Many tall buildings ______ in the past five years.

A. were built　　 B. have been built　　 C. will be built　 D. are built

49. The workers _____ two years on the bridge.

A. used　　 B. took　　 C. cost　　 D. spent

48. You _____ be thirsty and hungry after a long walk.

A. must　　 B. can　　　 C. have to　　　 D. should

47. My mother _______ her new coat today.

A. is putting on　 B. is dressing　　 C. is trying on　　 D. is wearing

在下列各题的四个答案中选择一个最佳答案

46. This morning I met an old friend in the street, I stopped _____ “Hello” to him.

A. saying　　 B to say　　 C. speaking　 　　D. to speak