2013高考英语(完形填空)倒计时冲刺50天(8)及答案
We have known for a long time that flowers of different plants open and close at different times of day.This is so __1__ that there seems to be no need to ask the reason for it.Yet no one __2__ understands why flowers open and close like this at particular times.The process is not as __3__ as we might think,as recent experiments have shown.In one study,flowers were kept in constant __4__.We might expect that the flowers,without any information about the time of day,did not open as they __5__ do.As a matter of fact,they __6__ to open at their usual time.This suggests that they have some mysterious(神秘的)way of knowing the __7__.Their sense of time does not __8__ information from the outside world;it is,so to speak,inside them,a kind of “inner clock”.
This __9__ may not seem to be very important.However,it was later found that not just plants but also __10__,including man,have this “inner clock” which __11__ the working of their bodies and influences their activities.Men,then,are also influenced by this mysterious __12__.Whether we wish it or not,it affects such things in our life as our need for sleep,our need for food.
In the past,this did not really __13__ because people lived in natural condition.In the __14__ world,things are different;now there are spacemen,airplane pilots and,in ordinary life,a lot of people who have to work at night.It would be very __15__,then,to know more about the “inner clock”.Such things as flowers might help us understand more about ourselves.
1.A.familiar B.strange C.similar D.special
2.A.partly B.personally C.really D.willingly