单选题
The normal human daily cycle of activity is of some 7-8 hours" sleep
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with some 16-17 hours" wakefulness and that the sleep normally coincides
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the hours of darkness. Our present
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is with how easily and to what extent this
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can be modified.
The question is no mere academic one. The ease with
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people can change from working in the day to working at night is a
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of growing importance in industry where automation
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round—the-clock working of machines. It normally
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from five days to one week for a person to adapt to a
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routine of sleep and wakefulness, sleeping
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the day and working at night.
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it is often the case in industry that shifts are changed every week. This
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that no sooner has he got used to one routine
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he has to change to another,
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much of his time is spent neither working nor sleeping very
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.
One answer would seem to be
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periods on each shift, a month, or even three months.
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, recent research has shown that people on such systems will revert to go back to their
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habits of sleep and wakefulness during the week-end and that this is quite enough to destroy any
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to night work built up during the week. The only real solution appears to be to hand over the night shift to those permanent night workers whose
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may persist through all weekends and holidays.
【答案解析】[解析] 本题考查“介词+关系代词”引导的定语从句的用法。关系代词在定语从句中作介词宾语时，从句常由“介词+关系代词”引导，如：The school in which he once studied is very famous. 此句的句子结构是：The ease(主语)+with...(介词+关系代词引导的定语从句)+is...，所以正确答案为C选项。
【答案解析】[解析] 本题考查介词的用法。句子的意思是说在白天睡觉晚上工作，此处应该选择during，因为during the day表示在这一天的时间里，表示的是持续性的一天，所以选A。表示具体的星期、日、月应该用on，如：on that day, on Friday, on March，表示年用in，如：in 1999，但是如果年月日一起就用on，如：on the 1st，1999。
【正确答案】
C
【答案解析】[解析] 本题考查对上下文的理解。上文提到“颠倒作息时间大约需要五天到一个星期，而后文又说在工厂里这种轮班工作经常是每周一换的”。工人们刚调整过来的作息时间又得换回去，这显然是“不幸地”。in comparison意为“比较”；in a word意为“总之”；therefore意为“因此，所以”，意思上不符合原文，所以选C。