用所给词的适当形式填空。

1. Jay sang the song ________ (beautiful).

2. The water in the river is _________ (harm). You can drink it without cooking.

3. When I passed the driving test, I thought I was the _________ (luck) person in the world.

4. Danny and Daniel are brothers, and their _________ (wife) are sisters. That's interesting.

5. This dress is very popular this year. Do you know who the ________ (design) is?

6. What do you think about the air _________ (pollute) in your hometown?

7. They stopped _________ (talk) and listened to their teacher.

8. Many people use computers in their _________ (day) lives.

某企业有5个分公司依次设置在同一条铁路线的沿线A、B、C、D、E站。现在该企业希望在该铁路沿线设立一个仓库，要求该仓库离这5个站的火车行驶距离之和最小。如用数轴表示该铁路线，A、B、C、 D、E各站的坐标依次为a、b、c、d、e(a＜b＜c＜d＜e)，则该仓库大致应设置在坐标 (30) 处。

A．c

B．(a+b+c+d+/5

C．(a+2b+3c+2d+/9

D．(a+4b+6c+4d+/16