2006年 考研英语（旧卷）阅读理解（四选一） 第 3 篇 · 31–35 题答案与解析

The extinction of large prehistoric animals is noted to suggest that 直接给出"提到 X 是为了说明什么"的固定问法，正是例证目的题的典型问法。

The extinction of large prehistoric animals is noted to suggest that 主干是 The extinction is noted to suggest that…，is noted to suggest 是"被提及以暗示"的被动结构，that 引出宾语从句作为答案空位；句中无陷阱，只需读懂"提到史前大动物灭绝这件事，是为了暗示____"。

• A)偷换概念

  large animals were vulnerable to the changing environment 说大型动物因环境变化而脆弱，但原文给出的原因是 The large, slow-growing animals were easy game, and were quickly hunted to extinction.，是"被人类捕猎"而非"环境变化"。

• B)答非所问

  small species survived as large animals disappeared 复述了 Smaller species survived.，原文确实有，但本题问的是"提到史前大动物灭绝是为了说明什么"，不是"史前发生了什么"——细节正确却非题干所要。

• C)✓ 正确
  • Now something similar could be happening in the oceans.↔large sea animals may face the same threat today
  • in the oceans↔large sea animals

  预判要求答案落在"今天的海洋大型生物 + 同样威胁 + 可能性"，C 项三要素齐备，是定位句的同义改写。

• D)与原文相反

  slow-growing fish outlive fast-growing ones 说慢生的鱼活得更久，但原文 The large, slow-growing animals were easy game, and were quickly hunted to extinction. 恰恰是"大型慢生的动物最先被猎杀灭绝"，方向反了。

We can infer from Dr. Myers and Dr. Worm's paper that 明确要求从论文内容推断，属典型推断题。

We can infer from Dr. Myers and Dr. Worm's paper that 主干是 We can infer that…，from 短语限定信息来源是这篇 paper；结构平铺直叙，无陷阱。

• A)✓ 正确
  • reduced on average by 80% within 15 years of the start of exploitation↔the stock of large predators in some old fisheries has reduced by 90%
  • In some long-fished areas↔in some old fisheries

  唯一在"老渔场"前提下给出合成结果 90% 的选项，与预判完全一致。

• B)偷换概念

  there are only half as many fisheries as there were 15 years ago 说渔场数量减半，但原文 it has halved again since then. 中 it 指代 the biomass of large predators（生物量），不是渔场数量。

• C)偷换概念

  the catch sizes in new fisheries are only 20% of the original amount 说渔获量只剩原来的 20%，但原文说的是 the biomass of large predators … is reduced on average by 80%——是"大型捕食者生物量"减 80%，不是"渔获量"。Dr. Worm 在第 3 段更明确指出 real difference between present and past is likely to be worse than the one recorded by changes in catch sizes，明确把 biomass 与 catch sizes 区分开。

• D)无中生有

  the number of large predators dropped faster in new fisheries than in the old 拿新老渔场的下降"速度"作比较，但原文只给"新渔场 15 年降 80%"与"老渔场后续再减半"两个事实，并未比较二者下降速率。

By saying "these figures are conservative" (Line 1, Paragraph 3), Dr. Worm means that 是典型的"作者说 X 意思是"问法，属词义句意题。

By saying "these figures are conservative" (Line 1, Paragraph 3), Dr. Worm means that 主干是 Dr. Worm means that…，by saying 是方式状语；括号内 (Line 1, Paragraph 3) 是定位线索，不是句子成分；结构无陷阱。

• A)答非所问

  fishing technology has improved rapidly 复述了 fishing technology has improved.，但这只是 Worm 给出的"为何数字偏低估"的原因之一，不是 conservative 这个词本身要表达的意思。

• B)偷换概念

  the catch-sizes are actually smaller than recorded 说"渔获量比记录的要小"，但原文说"真实损失比记录的渔获量变化反映的更严重"——是"生物量损失"被低估，不是"渔获量"本身被低估；catch sizes 在原文里恰恰是用来"做记录"的工具，不是被低估的对象。

• C)✓ 正确
  • the real difference between present and past is likely to be worse than the one recorded by changes in catch sizes↔the marine biomass has suffered a greater loss
  • these figures are conservative↔the marine biomass has suffered a greater loss

  唯一指向"真实损失比记录的更大"的选项，正是 conservative 一词在本段的工作义。

• D)无中生有

  the data collected so far are out of date 说数据"过时"，但原文从未提及数据时效性，只说数据偏低估——"低估"与"过时"是两回事。

Dr. Myers and other researchers hold that 问"他们主张什么"，答案就写在原文相应观点句里，属立场归属型细节题。

Dr. Myers and other researchers hold that 主干是 Dr. Myers and other researchers hold that…，hold that 引出宾语从句，宾语就是答案空位；句式平实，无陷阱。

• A)偷换概念

  people should look for a baseline that can work for a longer time 说要找"能用更长时间的基线"，但原文主张的不是"基线要长寿"，而是"基线参考的回望时段要拉长 / 要随变化漂移"；longer time 偷换了 shifting 的方向。

• B)偷换概念

  fisheries should keep their yields below 50% of the biomass 说"渔获量应低于生物量的 50%"，但原文 the maximum sustainable yield … comes when the biomass of a target species is about 50% of its original levels 说的是"当目标物种生物量为原始水平的 50% 时，可持续捕捞量最大"——50% 指生物量与原始量之比，不是渔获与生物量之比，且原文是"维持在 50% 左右"，不是"低于 50%"。

• C)过度推断

  the ocean biomass should be restored to its original level 说应把海洋生物量恢复到原始水平，但原文只说"生物量维持在原始量的约 50% 时可持续捕捞量最大"，从未主张"恢复到 100%"；这是把数据观察直接拔高到管理目标。

• D)✓ 正确
  • the "shifting baseline"↔people should adjust the fishing baseline to the changing situation
  • people have failed to detect the massive changes which have happened in the ocean because they have been looking back only a relatively short time into the past↔adjust the fishing baseline to the changing situation

  唯一抓住"基线随情况而调整"语义的选项，与定位句的核心主张一一对应。

The author seems to be mainly concerned with most fisheries' 用 mainly concerned with 直接问作者主要关注什么，是典型主旨题问法。

The author seems to be mainly concerned with most fisheries' 主干是 The author seems to be concerned with…，mainly 是程度修饰，most fisheries' 后省略了名词中心（即答案选项填入的那个名词），全句相当于"作者似乎主要关心的是大多数渔场的____"；属于第一步说明里提到的"题干是待补全的不完整陈述句，选项是延续"的形态。

• A)以偏概全

  management efficiency 说"管理效率"，但全文核心是数据所揭示的"生物量大幅下降被低估"，future management efforts must take into account 只是顺带提到管理应以此为参照，不是作者主要关切。

• B)✓ 正确
  • Most fisheries are well below that, which is a bad way to do business.↔biomass level
  • the biomass of large predators (animals that kill and eat other animals) in a new fishery is reduced on average by 80% within 15 years of the start of exploitation↔biomass level

  唯一既覆盖第 2、3、4 段中心术语 biomass、又对得上末段态度焦点的选项，是主线的一词归结。

• C)偷换概念

  catch-size limits 说"渔获量限额"，但原文里 catch sizes 出现是用来说明"靠渔获量记录会低估损失"，并不讨论该不该设上限；这是把术语挪用为不存在的话题。

• D)以偏概全

  technological application 说"技术应用"，但 fishing technology has improved 只是 Worm 解释"为什么数字偏低估"的三条原因之一，是支线证据，不是作者主要关切。