45. ----Shall I e-mail Sara about the meeting or shall I make a phone call?

　 　----_________.All I want is that everyone is present at the meeting on time.

　 A. By all means　　 　　　　　　　　　　　　 B. It’s up to you　　　

C. None of my business　 　　　　　　　　　 D. No problem

44. _____ you _____ more earlier, all the things ______ in a dreadful mess now.

　 A. If, packed; wouldn’t be　　　　　　 　　　 B. Had, packed; wouldn’t have been

　 C. Had, packed; wouldn’t be　　　　　　 　　 D. If, had packed; wouldn’t have been

43. _______was not until World War II ______the other two scientists managed to use new techniques to purify the chemical.

A. That; that　　　 B. It; then　　　　 　　 C. It; after　　　 　　　　 D. It; that

42. Can you telephone me _________ to arrange a meeting?

A. at your convenience 　　　　　　　　　　 B. for convenience　

C. on your convenience　　　　　　　 　　　 D. when you are convenient

41. So here are 16 things I wish they_______ me in school when I was young.

　 A. would teach　　 　 B. taught　　　　 　　　 C. had taught　　 　　　　 D. would have taught

40. _______hearing the gunshot, the crowd_____ in all directions.

A. At; fled　　　　 B. On; fled　　　 　　　　　　　 C. As soon as; fled　 　 D. When; ran