( )54. Training programs provided by companies are only recognized within the industry.

20. By the time the fire engines arrived, the house ____ to the ground.

9.

( )13. Talking to strangers on the Internet is absolutely safe.

66. In recent years, an increasing number of college students are involved in various volunteering causes. There is no denying that volunteers make great contributions to society. On the one hand, in any big events such as Beijing Olympic Games and Shanghai World Expo, human resources are surely in great demand. Whatever a volunteer can do is helpful for the event. On the other hand, students can reap great benefits from volunteering work. Various experiences in their volunteering practice guarantee their brighter future career.

( )51. Some education institutions provide programs which offer credits to help CE students get some recognized industry qualifications.

26. Before talking about the subject in details, ____.

46.To protect your computer system from virus infection, delete ___46___.

59. 这次会议所讨论的内容仅限于议程上的项目。

2. 

32. She had to ____ her umbrella from the Lost Property Office.

Conversation 28.