3．Science can't explain the power of pets，but many studies have shown that the company of pets can help lower blood pressure （血压） and raise chances of recovering from a heart attack，reduce loneliness and spread all-round good cheer．
Any owner will tall you how much joy a pet brings．For some，an animal provides more comfort than a husband/wife．A 2002study by Karen Allen of the State University of New York measured stress （紧张） levels and blood pressure in people-half of them pet owners-while they performed 5minutes of mental arithmetic （算术） or held a hand in ice water．Subjects completed the tasks alone，with a husband/wife，a close friend or with a pet．People with pets did it best．Those tested with their animal friends had smaller change in blood pressure and returned most quickly to baseline heart rates．With pets in the room，people also made fewer math mistakes than when doing in front of other companions．It seems people feel more relaxed （放松）around pets，says Allen，who thinks it may be because pets don't judge．
A study reported last fall suggests that having a pet dog not only raises your spirits but may also have an effect on your eating habits．Researchers at Northwestern Memorial Hospital spent a year studying 36fat people and their equally fat dogs on diet-and-exercise programs； a separate group of 56people without pets were put on a diet program．On average，people lost about I1pounds，or 5% of their body weight．Their dogs did even better，losing an average of 12pounds，more than 15% of their body weight．Dog owners didn't lose any more weight than those without dogs but，say researchers，got more exercise overall-mostly with their dogs-and found it worth doing．
67．What does the text mainly discuss？A
A．What pets bring to their owners．
B．How pets help people calm down．
C．People's opinions of keeping pets．
D．Pet's value in medical research．
68．We learn from the text that a person with heart disease has a better chance of getting well ifA
A．he has a pet companion
B．he has less stress of work
C．he often does mental arithmetic
D．he is taken care of by his family
69．According to Allen，why did the people do better with pets around when facing stressful tasks？C
A．They have lower blood pressure．
B．They become more patient．
C．They are less nervous．
D．They are in higher spirits．
70．The research mentioned in the last paragraph reports thatA
A．people with dogs did more exercise
B．dogs lost the same weight as people did
C．dogs liked exercise much more than people did
D．people without dogs found the program unhelpful．
分析 本文属于说明文阅读，作者主要向我们介绍了科学不能解释宠物对我们的影响，比如有宠物的陪伴可以帮助降低血压，提高心脏病恢复的机会，并且可以感到放松，拥有一只宠物狗也会改变你的饮食习惯，使你得到更多的锻炼．
解答 67．A 主旨大意题，通读全文可知本文主要讲述了宠物给它们的主人带来的好处，故选A．
68．A 细节理解题，根据第一段but many studies have shown that the company of pets can help lower blood pressure （血压） and raise chances of recovering from a heart attack，reduce loneliness and spread all-round good cheer．可知许多研究表明宠物的陪伴能帮助降低血压，提高心脏病恢复的机会，故选A．
69．C 细节理解题，根据第二段It seems people feel more relaxed （放松）around pets，says Allen，who thinks it may be because pets don't judge．可知艾伦认为人们与宠物在一起时会更放松，不紧张，因此面对压力时做的更好，故选C．
70．A 推理判断题，根据最后一段Dog owners didn't lose any more weight than those without dogs but，say researchers，got more exercise overall-mostly with their dogs-and found it worth doing．可知养狗的人们会更多的锻炼，故选A．
点评 做阅读理解时要快速的浏览全文，把握文章主旨大意，带着问题回到原文，寻找细节或概括相应的答案，最后要理清作者写作思路．
