从运用和功能上分，地铁电话系统可分为那几个子系统？

阅读与回答问题 。  

     Many people like to travel by plane, but I don’t like it because the airport is usually far from the city.

You have to get there early and wait for hours for the plane to take off and it is often late. You can’t open

the windows. You can’t choose the food. Planes are fast, but they still take hours to go out of the airport

and into the city.

     I like traveling by train. I think trains are safe. Railway stations are usually in cities. When you are late

for a train, you can catch another one. You can walk around in the train and open the windows. You can

see many interesting things on your way. I know it takes a little more time. I also like cars. You can start

your journey when you want to, and you don’t need to get to a railway station or a bus stop. Also you can carry many things with you in a car. But sometimes there are too many cars on the road.

1. Why do many people like to travel by plane?

2. What can you do in the train?

3. If you have to take a lot of things with you, how will you travel?

4. What is the bad thing about taking a car?

5. How do you like to travel? And why? ( 请你用一句话回答)

    I like to travel by __________ because ___________________.

在PowerPoint 2000中，若对图表对象设置动画和声音，应进入“自定义动画”对话框中的______选项卡。

A．顺序和时间

B．效果

C．图表效果

D．多媒体设置

新建文档WD22B.DOC，插入文件WD11A.DOC的内容。将正文部分左缩进2厘米，右缩进2.5厘米，行距22磅，居中对齐，存储为文件WD11B.DOC。

成角透视又称（）。

A、一点透视

B、两点透视

C、三点透视

D、四点透视

田气膨胀制冷装置压缩机增压系统进气温度应控制在（）℃范围内。

A.10～30

B.15～35

C.10～40

D.15～40