Across the world, mobile phones are very popular with young people. They think that the phones are more than a means of communication — having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has worried some health professionals. Some doctors are concerned that in the future many people will suffer from health problems because of the use of mobile phones. But mobile phone companies say that there is no proof that mobile phones are bad for health. On the other hand, why do some medical studies show changes in the brain cells of some people who use mobile phones? Signs of change in the tissue (组织) of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at a young age due to the fact that he couldn’t remember even simple tasks. The man had been talking on his mobile phone for about six hours a day for a couple of years. His family doctor blamed his mobile phone use. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it is better to use mobile phones less often. Use a normal phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. So, for now, it is wise not to use your mobile phone too often. 小题1:Why do young people buy mobile phones according to the passage? (No more than 11 words) (2 marks) _____________________________________________________________________ 小题2:Why did the salesman mentioned in the passage retire young? (No more than 7 words) (2 marks) ____________________________________________________________________ 小题3:What do the manufacturing companies think of the safety issue of mobile phones? (No more than 14 words) (3 marks) _____________________________________________________________________ 小题4:What’s the purpose of the author’s writing this passage?   (No more than 11 words) (3 marks) _____________________________________________________________________