2. 职称英语
  3. When you first drift off into slumber, your eyes will roll about a bit, your

When you first drift off into slumber, your eyes will roll about a bit, your

游客2025-01-18  18
问题     When you first drift off into slumber, your eyes will roll about a bit, your temperature will drop slightly, your muscles will relax, and your breathing will become quite regular. Your brain waves slow down a bit, with the alpha rhythm predominating for the first few minutes. This is the first stage of sleep. For the next 30 minutes or so, you will drift down through Stage 2 and Stage 3. The lower your stage of sleep, the slower your brain waves will be. About 40—60 minutes after you lose consciousness, you will reach the last stage. Your brain waves will show the delta rhythm.
    You may think that you stay at this deep stage all the rest of the night, but that turns out not to be the case. About 80 minutes after you fall into slumber, your activity cycle will increase slightly. The delta rhythm will disappear, to be replaced by the activity pattern of brain waves. Your eyes will begin to dart around under your closed eyelids. This period of Rapid Eye Movements lasts for 8—15 minutes and is called REM sleep. During both light and deep sleep, the muscles in your body are relaxed but capable of movement. As you slip into REM sleep, a very odd tiling occurs—most of the voluntary muscles in your body become paralyzed. Although your brain shows very rapid bursts of neural activity during REM sleep, your body is incapable of moving. REM sleep is accompanied by extensive muscular inhibition.  [br] The first paragraph of this passage tells us about________.
选项 A、the rhythms of brain waves
B、the daily activities of sleep
C、the stages of sleep in cycles
D、the daily activities in cycles
答案 C
解析 题目问第1段的主要内容。第1段分别提到了睡眠开始阶段，以及进入到第2、3和最后一个睡眠阶段的各种表现，由此可知，第1段的主要内容是介绍睡眠的4个阶段，因此答案为C项。A项“脑电波的节奏”、B项“睡眠的日常活动”和D项“睡眠阶段的日常活动”均与语境不符，可排除。
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