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　　When Sean Aiken bought a bike helmet(头盔), he never thought it would help him so soon．Only a week later, it saved his life．He was hit by a car while riding home from school in Tucson, Arizona．His bike was broken into pieces in the accident．But Sean was alive．His helmet protected him from serious head injury(负伤)．“I used to think helmets were unnecessary．I thought I would never get hurt,” Sean said．“But it can and will happen to you if you’re not careful．”Sean later spoke before the Tucson City Council about the need of bike-helmet laws．This led to a new Arizona law that requires people under the age of 18 to wear a bike helmet while cycling．

　　Fifteen-year-old Mike Jones of Sioux Falls, South Dakota, knows about safety．Two years ago, he was seriously hurt in a car accident．Mike hurt his head badly when he was thrown from a van．“I don’t know why I didn’t wear a safety belt that day．Now I always wear it,” Mike said．Today, he can still think of that experience．“I used to love sports, but I can’t do them anymore．I can’t risk(冒险)getting another serious injury,” he said．

　　Like Mike, many people around the U．S．are becoming more safety-wise．“Parents can’t watch kids every minute．Kids must know how to be safe．It’s in their control and power,” says Susan Gallagher, director of the Safety Network．

　　New technology is also helping to prevent injuries．More people than ever before use products such as fire alarms in their homes and seat belts in their cars．Most cyclists know that they should use bike helmets．New laws, such as the bike-helmet law Sean Aiken helped pass, are also making more people use these products．The number of serious injuries caused by car accidents and fires has gone down over the years．

Kids are taking action to help prevent injuries．Like Sean Aiken and Mike Jones, they know that safety works．

1．Did the helmet save Sean Aiken’s life?

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2．What does the new Arizona law require?

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3．Why was Mike Jones seriously hurt in a car accident?

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4．What things are mentioned to prevent injuries in the passage?

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5．What is the main idea of the passage?

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