2017届高考英语二轮复习 第一部分 专题增分练 课时17 书面表达（五）-求助信.doc

课时17 书面表达（五）-求助信 Ⅰ.阅读理解A Ever feel like youve been hit on the head after a bad nights sleep？ According to scientistst as unbelievable as it seems. A study found going without sleep for just one night causes changes in the brain similar to those that occur after a blow to the head. The researchers said the healthy young men examined in the study showed a sudden increase in the same chemicals which indicate brain damage. Professor Christian Benedict， of Uppsala University， Sweden， explained that the chemicals NSE and S-100B are biomarkers (生物指标) for brain damage(脑震荡). He saidwithout sleep for a night. This was not to the extent that would happen after a head injury， for instance， but it was still significant. During sleep， the brain cleans poisonous substances off itself.” Benedict also said previous studies which linked a lack of sleep with increased risk of Alzheimers， Parkinsons and multiple sclerosis could applaud his study. The rise of the chemicals in the blood after sleep loss may suggest not getting enough sleep contributes to a loss of brain tissue， he explained. Benedict， whose study is published in the journal Sleep， added， “In conclusion， the findings of our experiment indicate a good nights sleep may be critical to maintaining brain health.” A third of the UK population suffer from sleep-related problems， while the average person now sleeps for only seven hours a night， compared with almost nine a few decades ago. Many scientists believe irregular sleeping patterns lead to illnesses ranging from aches and pains to heart disease， while less than eight hours sleep a night can lower the IQ the next day. [语篇解读]　本文是一篇科普类说明文。科学家们发现睡眠不足对大脑造成的损伤接近头部重击。不足八小时的睡眠甚至会降低第二天的智商。1.If you dont sleep for a night， what will happen？ain damage will be like a head injury. C.You will suffer from concussion. D.The brain will get rid of poisonous substances. 解析：考查细节理解。文章第二段的“What we found was their