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Americans think that travel is good for you, some even think it can help one of the country's worst problems-crime (犯罪).    

Crime worries a lot of people. Every year, the number of crimes goes up and up. And many criminals (罪犯)are young. They often come from sad homes, with only one parent or no parents at all.

There are many young criminals in prison. But prison doesn't change them. Six or seven in ten will go back to crime when they come out of prison.

One man, Bob Burton, thought of a new idea. In the old days, young men had to live a difficult life on the road. They learned to be strong and brave, and to help theft friends ill time of danger. This helped them to grow into men. So Bob Burton started" Vision Quest".

He takes young criminals on a long, long journey with horses and wagons(马车), 3,000 miles through seven states. They are on the road for more than a year.

The young people on Vision Quest all have bad problems. Most of them have already spent time in prison. This is their last chance.    

It's hard work on the road. The work starts before the sun comes up. The boys and girls have to feed the horses. Some of them have never loved anyone before. But they can love their horse. That love can help them to a new life.

 Not all the young people on Vision Quest will leave crime behind them. Three or four in ten will one day_____________. Bob Burton is right. Travel can be good for you. Even today. Americans still say, " Go west, young man."

1.What’s the main idea of the passage?   

2.Which sentence in the passage is the closest in meaning to the following one?

The criminals are very unfortunate ,because they have single parent or they are orphans

3.Please fill in the blank in the passage with proper words or phrases to complete the sentence.(within ten words)    

4.What do you think of the meaning of the travel to the young men in the old days according to the passage?(within 30 words)

5.Translate the underlined sentence into Chinese.

不改变关系表中的属性个数但能减少元组个数的是______。

低瓦斯矿井进风（全风压通风）的主要运输巷道内使用架线电机车，巷道必须使用（）支护。

A.木支护

B.不燃性材料

C.钢铁

400V动力中心开关有几个位置？