题文
Is there a limit to the number of years that a person can expect to live? Can changes in life-style add years to one’s life? Throughout history people have sought answers to these questions and others.Various myths offer the hope of great longevity. In the imaginary land of Shangri-La, for example, people are said to lead a charmed existence for a thousand years. The Spanish explorer Ponce de Leon was convinced that he would find the Foundation of Youth in what is now the state of Florida. According to the Bible, Methuselah lived to be more than 900 years old.
The subject of longevity is fascinating, and scientists study individuals such as Jeanne Calment to learn about the aging process. Calment died in 1997 in Arles, France, at the age of 122. She never married, and she lived in her own apartment until moving to a retirement community when she was 109.
Most scientists agree that bodies will last, at best, about 125 years. This potential has changed little since modern human beings appeared more than 100 thousand years age. Recent improvements in medicine and the environment have extended life expectancy, especially for those from poorer parts of the world. It is not clear, however, whether such improvements will lengthen life expectancy beyond a certain point.
Life expectancy is the number of years an infant can be expected to live, given the conditions into which it is born. Life expectancy, therefore, is affected by nutrition, medical care, and social and political circumstances. An individual’s genetic makeup is also an important factor. Children from long-lived families can hope to enjoy long lives themselves. According to recent data, the average life expectancy worldwide in 1998 was 67 years. This can be compared with an average life expectancy of 77 in the United States.
In 1970 the average life expectancy worldwide was 61 years, or 6 years less than it was in 1998. This same period saw a drop in infant mortality -— the death of a child before the first birthday-—from 80 births out of 1,000 to 54 births out of 1,000. According to some researchers, the rise in the average life expectancy is due primarily to the drop in infant mortality. It is not so much that adults are living to an older age. It is, rather, that more people are living into adulthood because more children are surviving beyond their first birthdays.
小题1:Infant mortality is defined as ________ .A．the number of children born aliveB．the kinds of behavior typical of very young childrenC．the number of children, out of 1,000 births, who die before their first birthdayD．the typical and obvious thoughts of very young children小题2:Although it may be possible to improve the life expectancy of a particular group of people, ________ .A．it is more difficult to affect the rate of infant mortalityB．it is unlikely that one will be able to extend the potential life span of human beings in generalC．the process of evolution is extending the potential life span beyond 125 yearsD．the potential that bodies will last, at best, about 125 years has changed much since modern human beings appeared小题3:One can infer that people have at times imagined that ________ .A．people live longer in the state of FloridaB．a long life is a burden rather than a blessingC．it is possible to find a way to live for centuriesD．life expectancy is affected by a couple of factors小题4:One can conclude that ________ .A．the aging process can be stopped.B．the aging process is inevitable.C．life expectancy in the United States will soon reach 125 years.D．the average life expectancy worldwide is decreasing 题型：未知 难度：其他题型
答案
小题1:C
小题2:B
小题3:C
小题4:B
解析
人的寿命有局限吗？改变生活方式可以延长寿命吗？自古以来，古今中外的人们都在试图破解生命之谜，寻找长寿之方。然而科学家们却认为人的寿命除了受营养、医疗、社会和政治环境影响外，人的遗传基因也起着非常重要的作用，所以人的寿命不是可以无限延长的。
小题1:C 词意猜测题。根据末段infant mortality -— the death of a child before the first birthday-—from 80 births out of 1,000 to 54 births out of 1,000.可知infant mortality指的是婴儿死亡率，故C选项正确。
小题2:B根据文章第四段内容可知人的寿命受多种因素影响，比如营养、医疗、社会和政治环境而且人的遗传基因也起着非常重要的作用，由此推断人们的寿命不可能全部延长，所以B为正确选项。
小题3:C细节理解题。根据文章第二段的内容可知人们曾认为某些地方的人们能活到将近一千年，由此可知C选项正确。
小题4:B推理判断题。根据文中Most scientists agree that bodies will last, at best, about 125 years.以及下文Life expectancy, therefore, is affected by nutrition, medical care, and social and political circumstances.可知无论怎样想方设法延长寿命，人的死亡是不可避免的，所以B选项正确。
考点
据考高分专家说，试题“ Is there a limit to.....”主要考查你对 [政治经济类阅读 ]考点的理解。政治经济类阅读
政治经济类文章的概念：
要做好这类阅读，平时就要注意了解国内外发生的政治经济大事，掌握一定背景知识，对这类文章的叙述特点及内容安排有一定了解，还要扩展这方面的词汇。阅读这类文章，要抓住文章的核心，即文章整体和各段主要在说什么，也要注意段落之间的逻辑关系。
如何备考政治经济类阅读理解题：
【题型说明】政治经济类阅读文章是高考常选材料之一。该类文章时代气息浓郁，语言鲜活，但熟字新义词、超纲词及专业词语多，长句、难句多。政治类文章大多数是同学们感性趣的内容，读起来倒有似曾相识的感觉，经济类文章读起来就像是雾里看花，文章看完，一头雾水。再加之这类文章的命题侧重于词义猜测、推理判断和文章主旨，同学们对这类题材是望而生畏。
【备考策略】建立心理优势。针对不同体裁的文章，我们要采取相应的阅读方法和技巧。政治类文章多采用记叙文形式，我们可采取“顺读法”，以便抓关键语句，领会文章主旨；而经济类文章则多采用说明文形式，我们则可以采取“逆读法”，先读试题，再从文章中查找有用信息。若遇到的确难读的材料。千万不用着急，因为你觉得难，其他人也一定是同感。在高考前，我们就要有这种心理准备，高考试卷肯定有一、两篇难以阅读的材料。不过，我们平时可以有意识地从报刊杂志上找一些较难的阅读材料来阅读，以培养自己迎难而上的心理素质。
【答题方法】
1、寻找主干：
根据英语中五种基本句型结构，把句子中的主语、谓语、宾语、表语等主要成分找出来，其他成分如定语、状语、补语等则易于理解。找到了句子主干，句子的意思至少明白了一半。
2、剔除从句：
在一个长句中可能会出现若干个从句，在理解时，如果把各个从句剔除出来单独理解，然后把大意拼凑起来，整个长句的意思就会明白六、七分。
3、辨别分句：
一个长句如果是由几个并列、转折、递进、对比关系的分句组成，句中往往有表示这些分句关系的连接词，只要能弄清楚分句和分句之间的逻辑关系，再把各层分句的意思加以连贯，整个长句的句意基本上能跃然脑中。
4、寻找关键词：
如果一个句子看完，一点句意的感觉也没有，下下策就是抓住句中的关键词，通过关键词大体弄懂这个长句的意思。
