83. What is the biggest challenge shi is facing?
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B. 根据文章内容完成下列表格。
It seems that no one really knows why we sleep. There are two theories, but a theory(理论)is only an idea or a guess. Even scientists don’t know if these theories are correct or not.
One theory of sleep is called the “Repair Theory”. This theory says that during the day we use many important chemicals in our bodies and brains(脑). So we need sleep to make new chemicals which we use the following day.
Another theory is called the “Adaptive Theory”. This theory says that sleep developed gradually and naturally because on the one hand it stopped early humans and animals from wasting energy, on the other hand it kept themselves out of danger from the other animals that killed and ate them. In other words, sleep kept them safe and out of trouble. It was necessary for their survival(生存).
Whatever the reason for sleep, everyone sleeps and everyone dreams every night. Many times we don’t remember our dreams, but we still dream. Like sleep, no one knows exactly why we dream or what dreams mean. There have been many theories about dreams. Many cultures believe that dreams can foretell the future that they can tell us what will happen to us. Some psychologists and psychiatrists(精神病学家)believe that dreams tell us about our feelings and desires.
However some scientists now believe that dreams mean nothing at all------dreams are caused by the electrical activity in our brains while we sleep and our brains try to make a story out of these meaningless patterns(图案). In fact, the dreams seem crazy and without meaning sometimes because they are crazy and without any meaning at all.
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Theory |
Main ideas |
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Repair Theory |
84____________________________ |
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Adaptive
Theory |
85____________________________ |
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Three
different opinions about dreams |
a. 86__________________________ b. Dreams tell us about our feelings and desires. c. 87___________________________ |