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2013年职称英语等级考试理工类考前重点 注：此内容为《汇知考轻松-职称英语等级考试零起点辅导》课程于2013年3月5日第三次升级标记★★★的考试重点内容。为便于大家的学习，将此部分整成为Word文档，需要的考生朋友可以下载后自行打印。 该内容为考试时可能从书上出题的范围，一般来说会从这部分内容里边出题30分，为了您的考试过关，请不要只依赖于此部分内容！请尽量安排时间作全面的学习！各篇文章在《汇知考轻松-职称英语等级考试零起点辅导》课程软件中的位置文档已注明。 阅读理解部分 [C]第1篇 Making Light of Sleep （阅读理解C第六讲） All we have a clock located inside our brains. Similar to your bedside alarm clock, your internal clock runs on a 24-hour cycle. This cycle, called a circadian rhythm, helps control when you wake, when you eat and when you sleep. Somewhere around puberty, something happens in the timing of the biological clock. The clock pushes forward, so adolescents and teenagers are unable to fall asleep as early as they used to. When your mother tells you its time for bed, your body may be pushing you to stay up for several hours more. And the light coming from your computer screen or TV could be pushing you to stay up even later. This shift is natural for teenagers. But staying up very late and sleeping late can get your bodys clock out of sync with the cycle of light and dark. It can also make it hard to get out of bed in the morning and may bring other problems, too. Teenagers are put in a kind of a gray cloud when they dont get enough sleep, says Mary Carskadon, a sleep researcher at Brown University in Providence, RI. It affects their mood and their ability to think and learn. But just like your alarm clock, your internal clock can be reset. In fact, it automatically resets itself every day. How? By using the light, it gets through your eyes. Scientists have known for a long time that the light of day and the dark of night play important roles in setting our internal clocks. For years, researchers thought that the signals that synchronize the bodys clock were handled through the same pathways that we use to see. But recent discoveries show that the human eye has two separate light-sensing systems. One system allows us to see. The second system tells our body