Reading Comprehension
试题详情
文章：
| Line | There are recent reports of apparently drastic |
| declines in amphibian populations and of extinctions | |
| of a number of the world’s endangered amphibian | |
| species. These declines, if real, may be signs of a | |
| (5) | general trend toward extinction, and many |
| environmentalists have claimed that immediate | |
| environmental action is necessary to remedy | |
| this “amphibian crisis,” which, in their view, is an | |
| indicator of general and catastrophic environmental | |
| (10) | degradation due to human activity. |
| To evaluate these claims, it is useful to make a | |
| preliminary distinction that is far too often ignored. | |
| A declining population should not be confused with | |
| an endangered one. An endangered population is | |
| (15) | always rare, almost always small, and, by definition, |
| under constant threat of extinction even without a | |
| proximate cause in human activities. Its disappearance, | |
| however unfortunate, should come as no great | |
| surprise. Moreover, chance events—which may | |
| (20) | indicate nothing about the direction of trends in |
| population size—may lead to its extinction. The | |
| probability of extinction due to such random factors | |
| depends on the population size and is independent of | |
| the prevailing direction of change in that size. | |
| (25) | For biologists, population declines are potentially |
| more worrisome than extinctions. Persistent | |
| declines, especially in large populations, indicate a | |
| changed ecological context. Even here, distinctions | |
| must again be made among declines that are only | |
| (30) | apparent (in the sense that they are part of habitual |
| cycles or of normal fluctuations), declines that take | |
| a population to some lower but still acceptable | |
| level, and those that threaten extinction (e.g., by | |
| taking the number of individuals below the minimum | |
| (35) | viable population). Anecdotal reports of population |
| decreases cannot distinguish among these | |
| possibilities, and some amphibian populations have | |
| shown strong fluctuations in the past. | |
| It is indisputably true that there is simply not | |
| (40) | enough long-term scientific data on amphibian |
| populations to enable researchers to identify real | |
| declines in amphibian populations. Many fairly | |
| common amphibian species declared all but extinct | |
| after severe declines in the 1950s and 1960s | |
| (45) | have subsequently recovered, and so might |
| the apparently declining populations that have | |
| generated the current appearance of an amphibian | |
| crisis. Unfortunately, long-term data will not soon | |
| be forthcoming, and postponing environmental | |
| (50) | action while we wait for it may doom species and |
| whole ecosystems to extinction. |
题目：
Which of the following best describes the function of the sentence in lines 35–38 ?
选项:
A、To give an example of a particular kind of study
B、To cast doubt on an assertion made in the previous sentence
C、To raise an objection to a view presented in the first paragraph
D、To provide support for a view presented in the first paragraph
E、To introduce an idea that will be countered in the following paragraph
答案:
C
提问：
句子功能题--思路： 不是承上，就是起下， 选项CD说的是第一段内容 先排除 -- 选项E 与下一段内容无关 排除 --选项AB中 B 文中没有质疑--所以最后选A 答案是C 我后来理解是 第一段说 if real, may be signs of a general trend toward extinction， 定位句意思是 some amphibian populations have shown strong fluctuations in the past. 是数量的起伏变化 可能这一段驳斥了第一段 老师，我有以下两个问题 1.我不知道我后来分析的对不对 希望老师可以讲解一下 2. 句子功能题做题思路应该是怎样的？ 像这样跨文章内容比较大的， 我可能只看定位句附近。 谢谢老师
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