19．Rhythm of Life
Choosing the right time to sleep，the correct moment to make decisions，the best hour to eat-and even go into hospital-could be your key to perfect health．
Centuries after man discovered the rhythms（节奏、韵律） of the planets and the cycles of crops，scientists have learned that we too live by precise rhythms that govern everything from our basic bodily functions to mental skills．Man is a prisoner of time．
But it's not just the experts who are switching on to the way our bodies work．（71）F Prince Charles consults a chart which tells him when he will be at his peak on a physical，emotional and intellectual level．Boxer Frank Bruno is another who charts his bio-rhythms to plan for big fights．
（71）E Sleep，blood pressure，hormone levels and heartbeat all follow their own clocks，which may bear only slight relation to our man-made 24-hour cycle．
Research shows that in laboratory experiments when social signals and，most importantly，light indicators such as dawn are taken away，people lose touch with the 24-hour clock and sleeping patterns change．Temperature and heartbeat cycles lengthen and settle into"days"lasting about 25hours．
In the real world，light and dark keep adjusting internal clock to the 24-hour day． But the best indicator of performance is body temperature．As it falls from a 10p．m．high of 37.2℃to a pre-dawn low of 36.1℃，mental functions fall too．（73）D
The most famous example is the nuclear accident at Three Mile Island in the US．The three operators in the control room worked alternating（交替的） weeks of day，evening and night shifts．（74）G Investigators believe this caused the workers to overlook a warning light and fail to close an open valve．
Finding the secret of what makes us tick has long fascinated scientists and work done over the last decade has yielded important clues．（75）B For example，the time we eat may be important if we want to maximize intellectual or sporting performance．There is already evidence suggesting that the time when medicine is given to patients affects how well it works．
A．The rhythm of life is a slight beat．
B．The aim is to help us become more efficient（高效的）．
C．Jenny Hope claims to have tested their body clocks to the limit．
D．This is a key reason why shift work can cause so many problems．
E．Experts say every aspect of human bodies is influenced by daily rhythms．
F．Many people study the state of their bio-rhythms before making their daily plans．
G．Such a dangerous combination never gave their bodies'natural rhythms a chance to settle down．
分析 本文属于说明文阅读，作者通过这篇文章主要向我们描述了如何让时间变得高效的一些方法．
解答 71．F 推理判断题．根据上文提到But it's not just the experts who are switching on to the way our bodies work但这不仅仅专家打开我们身体工作的方式，许多人在制定日常计划之前研究他们的身体规律．故选F
72．E 推理判断题．根据下文提到Sleep，blood pressure，hormone levels and heartbeat all follow their own clocks，which may bear only slight relation to our man-made 24-hour cycle睡眠，血压，激素水平和心跳都有自己的生物钟，这与人为的24小时的规律有一点点关系，专家说身体的每个方面都会影响日常的规律．故选E
73．D 推理判断题．根据上文提到As it falls from a 10 p．m．high of 37.2℃to a pre-dawn low of 36.1℃，mental functions fall too当温度从上午10点37.2℃到黎明前的36.1℃，身体的功能也在下降，这就是轮班所导致的许多问题的原因．故选D
74．G 推理判断题．根据上文提到The three operators in the control room worked alternating（交替的） weeks of day，evening and night shifts在控制室的三个实验人员交替的工作，白天，晚上和夜晚，这种危险的联系不会让身体有机会平静下来．故选G
75．B 推理判断题．根据上文提到For example，the time we eat may be important if we want to maximize intellectual or sporting performance比如如果我们想扩大我们的知道或运动表现，我们所花费的时间就是很重要的，目标是帮我们变得更高效．故选B
点评 七选五阅读是完成性阅读，和完形填空很类似，不同的是一个选词，一个选句子．解题时，要注意上下文语境，充分考虑信息词（选项中和空格前后句子中相同或相近的词），选出最符合语境的句子．
