运输生产开始之时，也是运输消费开始之时，而运输生产过程结束，运输的消费过程也结束，这

物体的主视图与左视图都是等腰三角形，俯视图是一个圆和圆心，则这个物体是______．

People who like their traveling have their reasons. They believe that traveling can help them expand their field of view, especially in the geographical and historical sense. They also think that touring will give them more chances to enjoy different kinds of food and experience new things that would never be brought by other activities. But those who dislike traveling also have some reasons.

Traveling, in my opinion, dose more good than harm. Most importantly, it broadened our mind. We can get in touch with other civilization（文明）, culture, customs and ideas.

Through history, most people traveled because of necessity —not for pleasure. People traveled just in order to remain alive. They searched for food to eat or places to live in. They sometimes ran away from enemies. This is not to say that no one ever traveled just for the fun of it. In ancient times, for example, rich Romans traveled all the way to Greece to take part in the Olympic Games, and festivals. Of course, some people decided to travel just out of curiosity. They wanted to find out what it looked like beyond the horizon（地平线）. Also business travel has been going on for centuries. Traders could not only make money but also learn to speak several languages and be introduced to different cultures.

So, traveling does enrich our mind and draw new ideas to us. There is no doubt that we can get much from it.

小题1:How many reasons for traveling are mentioned in Paragraph 3?

A．Three

B．Four

C．Five

D．Six小题2:In the writer’s opinion, traveling can be _______.

A．expensive

B．funny

C．helpful

D．tiring小题3:What’s the main idea of this passage?

A．Different kinds of traveling.

B．Traveling enriches our mind.

C．Ways to enjoy yourself while traveling.

D．The advantages and disadvantages of traveling.

机车柴油机气缸套的冷却水采用（）密封。

A、石棉垫

B、密封胶圈

C、法兰

D、铁皮垫

施工保证措施包括（）

A.质量保证措施

B.安全保证措施

C.进度保证措施

D.文明施工措施

E.环境保护措施

读某半球大气环流图，回答下列问题。

此时，图示半球的节气可能是（）

A．春分

B．夏至

C．秋分

D．冬至