49. --- I’m sorry, but there’s no smoking on this flight.

　　 --- Oh, I ______ that. Sorry, I won’t again.

　　 A. don’t know　 B. didn’t know C. won’t know D. haven’t known

48. It is when the plane ______ that you’d better find out at the booking office.

　　 A. would take off　 B. had taken off　 C. was taking off　 D. is taking off

47. The baby is generally healthy, but every now and then he ______ a cold.

　　 A. has caught　 B. is catching　 C. will catch　 D. does catch

46. --- Each of the students, working hard at their lessons, ______ the book.

　　 --- So have I.

　　 A. is reading　　　 B. has read　　　　 C. reading　　　 D. reads

45. --- I dropped in at your house at about ten last night, but you weren’t in.

　　 --- I ______ regular exercises at the club.

　 　A. did　　　　 B. was doing　　　 C. had done　　 D. have been doing

44. --- Who’s the man over there?

　 　--- It’s Jack.

　 　--- Oh? ______ in Italy.

　　 A. I think he’s　 B. I’ve thought he’s been C. I thought he was　 D. I’d thought he’d been

43. With the development of science, more new technology ______ to the field of IT.

　　 A. has introduced　 B. is being introduced C. is introduced　 D. was introduced

42. --- Got your driving license?

　 --- No. I __ too busy to have enough practice, so I didn’t take the driving test last week. I’m going to next week.

　　 A. was　　　　 B. have been　　　 C. am　　　　　 D. had been

41. --- Excuse me, sir. Would you do me a favour?

　　 --- Of course. What is it?

　 　--- I ______ if you could take me to the station.

　 　A. would wonder　 B. did wonder　 C. was wondering　 D. had wondered

40. --- How are you planning to travel to Shanghai?

　 　--- I ______ yet, but I ______ taking a train.

　 　A. didn’t decide; am considering　　 B. haven’t decided; consider

　 　C. haven’t decided; am considering　 D. hadn’t decided; have considered