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Is talking on a mobile phone hazardous to your health?It is difficult to know for sure.Some research suggests that heavy users of mobile phones are at a greater risk of developing brain tumors.However,many other studies suggest there are no links between cancer and mobile phone use.
The main problem with the current research is that mobile phones have only been popular since the 1990s.As a result,it is impossible to study the long-term exposure of mobile phone use.This concerns many health professionals who point out that many cancers take at least ten years to develop.Another concern about these studies is that many have been funded by those who benefit financially from the mobile phone industry.
Over three billion people use mobile phone on a daily basis,and many talk for more than an hour a day.Mobile phone antennas are similar to microwave ovens.While both rely on electromagnetic radiation,the radio waves in mobile phones are lower in radio frequency(RF).
Microwave ovens have enough RF to cook food and are therefore known to be dangerous to human tissues.However,the concern is that the lower frequency radio waves that mobile phones rely on may also be dangerous.It seems logical that holding a heat source near your brain for a long period of time is a potential health hazard.Mobile phones get hot when they are phoned for a long period of time.
Some researchers believe that over types of wireless technology may also be dangerous to human health,including laptops,cordless phones,and gaming consoles.Organizations that are concerned about the effects of Electromagnetic Radiation(EMR)suggest replacing all cordless devices with wired ones.They say that many cordless phones emit dangerous levels of EMR even when they are not in use.They even suggest keeping electronic devices,such as computers and alarm clocks out of bedrooms,or at least six feet from your pillow.
Other wireless technology may also be hazardous to our health.A growing number of professionals worldwide are recommending that mobile phone users should use their phones carefully until more definitive studies can be conducted.They recommend that adults use headsets or speaker phones and that children and teens,whose brain tissues are still developing use mobile phones only for emergencies.Concerned medical experts use the example of tobacco to illustrate the potential risks.Many years ago,people smoked freely and were not concerned about the effects of cigarettes on their health.Today people know that cigarettes cause lung cancer,though it is still unknown exactly how or why.Some doctors fear that the same thing will happen with devices such as mobile phones.
Which of the following is TRUE?查看材料
细节题。根据第二段中的“…many cancers take at least ten years to develop”司知D项正确。根据第一段中的“Is talking on a mobile phone hazardous to your health?It is difficult to know for sure”可知，目前并未确定手机对健康有害，故排除A。根据第22段中的“The main problem with the current research is that mobile phones have only been popular since the lgg0s”可排除B。根据第二段中的“…it is impossible to study the long-terill exposure of mobile phone use”可排除C。故本题选D。
有“泥土诗人”之称的诗人是（）。
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①不惑②垂髫③花甲④加冠⑤而立⑥古稀⑦半百
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