CET6：大学英语六级考试真题演练(第22期)

单选

36 to 40 are based on the .

We all know that the human daily cycle of is of some 7-8 hours’ sleep with some 16-17 hours’ and that, , the sleep with the hours of . Our is with how and to what this cycle can be .

The is no mere one. The ease, for , with which can from in the day to at night is a of in where calls for round-the-clock of . It takes from five days to one week for a to adapt to of sleep and , the day and at night. , it is often the case in that are every week; a may work from 12 to 8 a.m. one week,8 a.m. to 4 p.m. the next六级考试真题, and 4 p.m. to 12 the third and so on. This means that no has he got used to one than he has to to , so that much of his time is spent nor very .

The only real to be to hand over the night shift to a of night . An study of the life and of night-shift was out by Brown in 1957. She found a high (发生率) of sleep and other among those on day and night ,but no of these among those on night work.

This then to be the best long-term六级考试真题, but may be done to the of day and night work by those who can adapt most to the of . One way of when a has is by his body . in work will have a high the hours of and a low one at night; when they to night work the will only go back to match the new and the speed with which it does so , , the of the body as a whole, in terms of . , by body at of two hours the of it can be seen how a can adapt to a , and this could be used as a basis for . So far, , such a form of does not seem to have been in .

36.Why is the of “how can get used to at night” not a mere ?

A) few like to the cycle of sleep and .

B) sleep with the hours of .

C) are to work at night in some of .

D) shift work in to their .

37.The main of the round-the-clock lies in .

A) the about to the by the of

B) the of the daily life cycle of who have to too

C) the fact that at night are often less

D) the fact that it is to find a of good night

38.The best for the 24-hour seems to be .

A) to at

B) to have

C) to for some to work on night only

D) to for night

39.It is to find out if a has to the of by his body .

A) body when the cycle of sleep and

B) body when he to night shift or back

C) the when the is

D) have when they are

40.Which of the is NOT TRUE?

A) Body may serve as an of a ’s .

B) The of a of night shift has to be the best to of the round-the-clock .

C) body at can show how a to the of .

D) sleep less among those on night or day .