55.She picked up 10000 yuan (　　 )accident on her way to school.

54.She took my bag (　　　 )mistake in the shop.

53.He didn’t arrive at the airport (　　　 )12 o’clock.

52.His bike broke (　　　 ),and he had to have it repaired.

52.The books were best –sellers,and sold (　　 )quickly.

51.We must put our time (　　 )good use ,because time is very valuable for us.

50.Whatever difficulties we have, we must hold (　　 )(　　　 )our dream.

49.He felt good (　　　 )teaching students English.

48.(　　　 )your next vacation,why not go to UK?

47.The actor gave lots of money (　　　 )(　　　　 )the poor.