大气中微生物主要来源于（） A.农业 B.畜牧业 C.地球表面 D.工业 E.海洋

阅读理解。

    The Beijing Olympic Games are getting closer and closer. Are you looking forward to the excitement

ahead? To cheering on stars like Yao Ming and Liu Xiang?

    On April 15, more than 7 million tickets went on sale. If you can use the Internet, go to

www.tickets.beijing2008.cn., Or you can go to the Bank of China to book a ticket. But there's no hurry.

Any time before June 30, you can book a ticket to the opening and closing ceremonies. You can also order

tickets to 28 sports events including basketball, football and swimming.

    Whether you book tickets early or on the last day, you have an equal chance of getting one. If too many

people want to see the same event, a computer will decide who are the lucky ones. You may worry that

your pocket money will not be enough for a ticket. But the fact is tickets to the games are cheap. What's

more, students can get even cheaper tickets-for 10 yuan or less.

    Tickets for your parents aren't expensive, either. More than half are 100 yuan or less. The most expensive

tickets cost 5,000 yuan. They are for the opening ceremony. It will be held on August 8, 2008.

1. When will the Beijing Olympic Games start? [ ]

A. On August 8, 2008.

B. On April 15, 2008.

C. On June 30, 2008.

D. We don't know.

2. Which of the following is NOT true? [ ]

A. Yao Ming and Liu Xiang are world-famous Chinese athletes.

B. You can buy the tickets either in Bank of China or on the Internet.

C. The earlier you book the tickets, the more chances you have of getting them.

D. You can buy tickets any time before June 30.

3. If there are not enough tickets to the same event and you are lucky to get one, whom will you thank? [ ]

A. The tickets company.

B. The computer.

C. The Olympic Committee.

D. The government.

下列各句中，加粗的词语使用恰当的一项是[ ]

A．关于“千军万马挤独木桥”的高考压力现象，《国家中长期教育改革和发展规划纲要》提出，我国要逐步形成分类考试、综合评价、多元录取相结合的考试招生制度。

B．中国政府已庄重宣布，虽然中国的经济发展受国际金融危机的影响，遇到一些困难，但中国政府会兑现承诺，绝不失言。

C．随着一批实力雄厚的房地产项目落户本市，人们发现在不经意间，这个南部新城刮起了一种时尚健康、宜室宜家的居家风潮。

D．“两会”马上要开了，我有个不情之请，就是想请 * * 在两会期间到网上来，在线和全世界的华人网民聊聊天，谈谈国事、家事、大小事——某网友在网上留言。

右图是人体反射弧的示意图，请据图回答，如果A代表手部皮肤内的感受器，则神经冲动的传导方向是（  ）

A．A→B→C→D→E

B．E→D→C→B→A

C．C→B→D→E→A

D．B→C→A→D→E

对于胸椎有持久性创伤者的检查，正确的是（）

A.应作关节活动范围检查以排除压缩性骨折

B.椎体叩痛对诊断椎体骨折不敏感

C.应完成心肺、腹部器官与皮肤的彻底检查

D.不需作放射摄影，除非症状持续超过2～4周

E.感觉变化无助于诊断

用雷诺数判别流态的方法如下：Re≤2000为层流，Re>2000为紊流。