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2020年12月英语四级真题第3套 Part III Section C (2)
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2020年12月英语四级真题第3套 Part III Section C (2)

说明文 · 阅读理解（四选一） · 真题文章逐层精读

本页是 2020年12月英语四级真题第3套 Part III Section C (2) 文章的精读视角页——这篇说明文全文 346 词、8 段，CEFR 难度 B2（B2 级在英语四级文章中占 46%），作者立场为「客观中立」；英文原文之外，本篇已有的 11 项精读维度逐项展开，其中能迁移到其他英语四级真题文章的判断方法（篇章结构、修辞、言外之意、作者态度、体裁速判）随各维度一并讲透。

精读最佳实践

本页解析里的段号（P1）都可以点——点一下，原文在顶部翻开并定位到该段，解析引用的原文同步标亮；合上原文，你还停在刚才读到的位置。点 P1 试试。

PASSAGE · 文章原文

8 段英文原文

以下为2020年12月英语四级真题第3套 Part III Section C (2) 的阅读理解（四选一）原文，共 8 段。左侧 P1–P8 是段落编号——本页全部解析（结构、逐段、修辞、自检题）都以它为坐标回指原文，点击解析里的段号，原文即在顶部翻开并定位到该段、引用的原文同步标亮；合上原文仍停在当前阅读位置。原文保持卷面形态，不带翻译与标注。

The terms "global warming" and "climate change" are used by many, seemingly interchangeably. But do they really mean the same thing?

Scientists shaped the history of the terms while attempting to accurately describe how humans continue to alter the planet. Later, political strategists adopted the terms to influence public opinion.

In 1975, geochemist Wallace Broecker introduced the term "climate change" in an article published by Science. In 1979, a National Academy of Sciences report used the term "global warming" to define increases in the Earth's average surface temperature, while "climate change" more broadly referred to the numerous effects of this increase, such as sea-level rise and ocean acidification(酸化).

During the following decades, some industrialists and politicians launched a campaign to sow doubt in the minds of the American public about the ability of fossil-fuel use, deforestation and other human activities to influence the planet's climate.

Word use played a critical role in developing that doubt. For example, the language and polls expert Frank Luntz wrote a memo encouraging the use of "climate change" because the phrase sounded less scary than "global warming," reported the Guardian.

However, Luntz's recommendation wasn't necessary. A Google Ngram Viewer chart shows that by 1993 climate change was already more commonly used in books than global warming. By the end of the next decade both words were used more frequently, and climate change was used nearly twice as often as global warming.

NASA used the term "climate change" because it more accurately reflects the wide range of changes to the planet caused by increasing amounts of greenhouse gases in the atmosphere.

The debate isn't new. A century ago, chemist Svante Arrhenius started one of the first debates over the potential for humans to influence the planet's climate. Arrhenius calculated the capability of carbon dioxide to trap heat in the Earth's atmosphere, but other chemists disagreed. Some argued that humans weren't producing enough greenhouse gases, while others claimed the effects would be tiny. Now, of course, we know that whatever you call it, human behavior is warming the planet, with grave consequences ahead.

PARAGRAPHS · 逐段精读

8 段逐段主旨与解读

逐段拆解2020年12月英语四级真题第3套 的这篇原文——每段给出英文段落主旨、段落标题与中文解读，并提炼一条「这段为什么这样读」的具体方法。

  1. P1

    Are the Terms the Same?

    The paragraph raises the question of whether global warming and climate change have the same meaning.

    本段在全文中承担引题作用，通过“看似 interchangeable、实则待辨”的张力，引出文章对两个术语的 origins、区别及公共使用变化的系统说明。

    抓住设问
  2. P2

    Science and Politics Shape the Terms

    The terms were shaped first by scientific needs and later by political efforts to influence public opinion.

    本段是全文的 roadmap，它预先搭起“科学起源—政治利用”两条线索；第3段将展开 scientific history，第4至6段将具体说明 political influence。

    并列双主体
  3. P3

    The Scientific Distinction Between the Terms

    Scientific usage distinguished global warming as rising average temperature from climate change as its broader effects.

    本段为全文提供最核心的 scientific clarification，直接支撑文章主旨中“climate change 更准确描述广泛环境影响”这一判断，也为后文讨论词语选择奠定标准。

    定义比范围
  4. P4

    A Campaign to Create Doubt

    Some industrialists and politicians tried to make the public doubt humanity's role in climate change.

    本段把文章从科学定义推进到社会政治层面，解释术语之争为何不仅是 language issue，也与公众是否相信人类责任密切相关。

    谁在质疑什么
  5. P5

    How Softer Wording Shaped Opinion

    Political messaging favored climate change because it sounded less frightening than global warming.

    本段具体解释了政治操控的 language mechanism：通过选择听起来 less scary 的词，传播者可减弱公众的危机感，从而落实第2段所说的 influence public opinion。

    首句统领例证
  6. P6

    The Rise of Climate Change in Usage

    Climate change became more widely used than global warming independently of Luntz's advice.

    本段避免把术语变化简单归结为政治人物的个人策略，并以 usage data 补充说明 climate change 流行具有更广泛的社会语言现实。

    转折统领数据
  7. P7

    Why NASA Uses Climate Change

    NASA uses climate change because it more accurately covers the broad effects of greenhouse gases.

    本段回扣第3段的科学区分，并借 NASA 的权威立场强化全文结论：相较于只强调升温的 global warming，climate change 的覆盖范围更完整、更准确。

    抓住因果依据
  8. P8

    From Early Debate to Scientific Certainty

    Although scientists once debated human influence on climate, current evidence confirms that human behavior is warming the planet.

    本段作为结尾，将术语讨论提升到不可回避的事实层面：无论称作 global warming 还是 climate change，human behavior 正在造成变暖及 grave consequences，从而收束全文。

    今昔对照落结论
SELF CHECK · 段落自检题

8 道逐段细节自检题

针对2020年12月英语四级真题第3套这篇原文，每段配 1 道细节题（ 1 个正确项 + 5 个干扰项 ，由懒笔记精读引擎基于本段命制，非试卷原题）。 选项默认中性；点「显示答案与解析」展开正确项、解析与最快解法，现代浏览器会同步高亮正确选项。

  1. 第 1 段 定位词 global warming climate change

    What question is raised about the terms “global warming” and “climate change”?

    • A Why scientists prefer the term “climate change.”
    • B How greenhouse gases raise the Earth's temperature.
    • C Whether the two terms truly have the same meaning.
    • D When the phrase “global warming” first appeared.
    • E Which human activity causes the most climate damage.
    • F Whether public opinion accepts scientific findings.
    显示答案与解析 收起答案与解析

    正确答案：C

    正确项把原文的 do they really mean the same thing? 做了同义改写：really 对应 truly，mean the same thing 对应 have the same meaning。障碍在于题目没有直接问 definition，而是问作者 raised 的 question；考生必须识别问句的逻辑焦点是“同义与否”。

    双词同屏扫 时间极紧时，不必从头读全文。直接用题干中带引号的 global warming 和 climate change 做“双词同屏扫描”，可立即锁定 第1段；随后只比较选项中是否保留“same meaning”这一关系骨架，保留该骨架的正确项即为答案。

  2. 第 2 段 定位词 political strategists terms

    What did political strategists do with the two terms?

    • A They coined the terms to measure surface temperatures.
    • B They used the terms to describe planetary changes accurately.
    • C They rejected both terms as scientifically misleading.
    • D They adopted the terms to influence public opinion.
    • E They proved that human activity changes the climate.
    • F They replaced scientific reports with public polls.
    显示答案与解析 收起答案与解析

    正确答案：D

    选项完整保留 adopted the terms to influence public opinion 的动作—目的链。命题障碍是段内前半句也出现 scientists shaped，考生若只记得“科学家与术语”而忽略主语切换，就可能误选主体错配项。

    主语验尸法 用 political strategists 这个低频身份词直达 第2段，不要被全文的 climate 主题词拖慢。采用“主语验尸法”：逐项只核验“谁 + 为了什么”，凡是把正确项以外的科学目的或证明责任塞给该主语的选项，立即排除。

  3. 第 3 段 定位词 1979 global warming

    How did the 1979 report distinguish “global warming” from “climate change”?

    • A It treated climate change as a cause of global warming.
    • B It limited climate change to ocean acidification alone.
    • C It used both terms only for sea-level rise.
    • D It defined global warming as any human effect on the planet.
    • E It defined global warming as rising average surface temperature and climate change as its broader effects.
    • F It concluded that the two terms should no longer be used.
    显示答案与解析 收起答案与解析

    正确答案：E

    该项严格保留了定义层级：global warming 是 increases in average surface temperature，climate change 是 this increase 的 numerous effects。障碍在于正确项用 its broader effects 概括 sea-level rise 和 ocean acidification，考生需识别概括没有改变因果与范围。

    年份切对照句 直接数字扫描 1979，锁定 第3段 后只读含 while 的一句。用“左右栏压缩”：把 while 左侧记为术语 A 的 definition，右侧记为术语 B 的 scope；能同时保住这两个栏位且不倒置关系的正确项即为答案。

  4. 第 4 段 定位词 industrialists and politicians campaign

    What was the campaign launched by some industrialists and politicians intended to do?

    • A To persuade the public to reduce fossil-fuel use immediately.
    • B To provide scientific proof of deforestation's effects.
    • C To encourage scientists to develop new climate terms.
    • D To explain the consequences of ocean acidification.
    • E To reach a political agreement on climate policy.
    • F To make the American public doubt that human activities can affect the climate.
    显示答案与解析 收起答案与解析

    正确答案：F

    选项把 sow doubt in the minds of the American public 与 human activities to influence the planet's climate 准确同义改写。障碍在于原文结构较长，插入 fossil-fuel use、deforestation 等例子；正确项删去例子却保留了“对象—怀疑内容”的主干。

    截取目的不定式 以 industrialists and politicians 这一罕见双身份组合锁定 第4段，随后执行“to 不定式截取法”：从 launched 一直读到第一个完整的 to do purpose。选项中只有正确项保留“公众怀疑 + 人类活动影响”的双层宾语。

  5. 第 5 段 定位词 Frank Luntz the use

    Why did Frank Luntz encourage the use of “climate change”?

    • A Because the phrase sounded less frightening than “global warming.”
    • B Because it was already used more often in books.
    • C Because it referred only to temperature increases.
    • D Because NASA had officially selected it.
    • E Because the Guardian created the phrase.
    • F Because it could prove that climate risks were small.
    显示答案与解析 收起答案与解析

    正确答案：A

    sounded less frightening 是 sounded less scary 的等义替换，than “global warming” 保留比较对象。障碍在于原文先有 word use played a critical role 的概括句，后有例子；考生须进入 example，不能把“起关键作用”误当作具体原因。

    情感语义场筛选 先用 Frank Luntz 这个人名锁到 第5段，再只读其后包含 because 的半句。使用“语义场排除”：正确项应属于 scary、fear、tone 这一情感语言场；统计、机构、科学证明语义场的选项即使词面相关也排除。

  6. 第 6 段 定位词 Google Ngram Viewer climate change

    What does the Google Ngram Viewer chart indicate about the use of the two terms?

    • A “Global warming” was used almost twice as often as “climate change.”
    • B By 1993, “climate change” was already more common than “global warming,” and both terms later increased in use.
    • C Both terms became less frequent after 1993.
    • D “Climate change” was not used in books before 1993.
    • E The chart showed that the two terms were used equally often.
    • F The chart explained why scientists changed their terminology.
    显示答案与解析 收起答案与解析

    正确答案：B

    该项保留两项关键数据关系：一是到 1993 年 climate change 已经 more common，二是后来 both words were used more frequently。它没有把 nearly twice 的近似程度误写为精确两倍。障碍在于正确项整合了两个时间层次，考生若只抓后半句可能漏掉“谁更常用”。

    双箭头验趋势 直接扫描 Google Ngram Viewer 至 第6段，采用“箭头速记法”：给两个术语各画频率箭头，再在较高者旁标记“约两倍”。不翻译整句，只核对选项的比较方向和上升方向；与两条箭头完全一致的正确项即为答案。

  7. 第 7 段 定位词 NASA the term

    Why did NASA use the term “climate change”?

    • A Because it refers only to the Earth's surface temperature.
    • B Because it sounds less scary to the public.
    • C Because it more accurately covers the wide range of changes caused by rising greenhouse gases.
    • D Because it had become the only term used in books.
    • E Because it denies the role of human behavior.
    • F Because it was introduced by the National Academy of Sciences.
    显示答案与解析 收起答案与解析

    正确答案：C

    选项用 covers 替换 reflects，用 rising greenhouse gases 概括 increasing amounts of greenhouse gases，但保留 more accurately、wide range 和 caused by 的完整逻辑。障碍是正确项没有逐个列出变化现象，要求考生接受“范围概括”而非寻找原句逐字复现。

    因为句三块压缩 以 NASA 三个大写字母直达 第7段，忽略前后历史材料。用“because 后半句压缩法”：将理由压成“更准确 + 范围广 + 温室气体造成”，再找同时具备三块信息的正确项；任何只谈 scary 或频率的选项都不必细读。

  8. 第 8 段 定位词 Arrhenius chemists

    What was one objection raised by chemists who disagreed with Arrhenius?

    • A Carbon dioxide could not trap heat in the atmosphere.
    • B Sea-level rise was the only serious consequence of warming.
    • C Human behavior was already warming the planet with grave consequences.
    • D Humans were not producing enough greenhouse gases.
    • E Political strategists had manipulated public opinion.
    • F The term “climate change” was scientifically inaccurate.
    显示答案与解析 收起答案与解析

    正确答案：D

    该项直接改写 Some argued that humans weren't producing enough greenhouse gases，没有添加新的因果或程度信息。障碍在于段内还有另一反对理由 effects would be tiny，二者都属于反对意见；本题选用其中一项，考生需避免把它误认为作者的当前结论。

    发言标签切割 用 Arrhenius 定位 第8段 后，实施“发言标签法”：只读 Some argued 和 others claimed 后的内容，完全跳过段末 Now, of course 的现代总结。正确项属于前两条带反对标签的论据之一；含 now、grave consequences 等结论语气的选项立即排除。

STRUCTURE · 篇章结构

8 个意群的说明文骨架

按说明文 的行文骨架切分意群，每个意群标注它覆盖的段落与对主旨的作用——逐段读完后回到这里俯瞰全篇，能看清作者为什么按这个顺序行文。

  1. P1

    提出问题引发思考

    文章开篇通过 question 的形式提出 core issue，即 global warming 和 climate change 这两个 terms 是否 mean the same thing，这是典型的 problem-posing approach，用 seemingly interchangeably 来 highlight 公众认知中的 confusion，从而 establish 整篇说明文的 central question。

    这个 opening paragraph 通过 rhetorical question 建立了说明文的 explanatory focus，为后文 trace 这两个术语的 historical development 和 distinction 设定了 framework，是 expository text 中常见的 problem-statement strategy。

    引出术语辨析对象
  2. P2

    概述术语演变的双重驱动力

    这个 transitional paragraph 提供了 macro-level answer，指出这些 terms 的 history 是由两股 forces 塑造的：scientists 追求 accurate description，以及 political strategists 进行 opinion manipulation。这是 overview statement，为后文的 detailed chronological explanation 提供了 framework。

    作为 bridge paragraph，它 connects 开篇的 question 和后续的 detailed exposition，通过 identify 两个 driving forces（scientific 和 political），这个 segment 为说明文的 dual-track structure 搭建了 organizational framework，是 expository writing 中的 preview statement。

    概括演变动因
  3. P3

    追溯术语的科学起源

    这个 paragraph 聚焦于 scientific origin，通过 chronological markers（1975, 1979）展示了这两个 terms 是如何在 scientific community 中被 defined 和 differentiated 的。Broecker introduced climate change，而 National Academy of Sciences report 建立了 precise distinction：global warming 指 temperature increase，climate change 指 broader effects。

    这是 expository text 中 first major supporting section，它 addresses 前面 framework 中提到的 scientific dimension。通过 provide authoritative definitions 和 trace chronological development，这个 segment establishes factual foundation，让 readers understand 这些 terms 的 technical meanings before exploring political manipulation。

    阐明科学定义
  4. P4

    揭示政治操纵的开端

    这个 paragraph 标志着从 scientific track 到 political track 的 crucial shift。通过 during the following decades 这个 temporal connector，text 转向 describe 另一股 force：industrialists 和 politicians 如何 launch campaign 来 create doubt about human influence on climate。关键词 sow doubt 揭示了 deliberate manipulation。

    这个 segment 开启了说明文的 second major explanation track，responding to framework paragraph 中提到的 political strategists' role。它 establishes 一个 contrast：科学家追求 accuracy，而政界人士追求 influence public opinion，这种 juxtaposition 是 expository writing 中展示 complexity 的常用手法。

    引入政治干预
  5. P5

    剖析语言操纵的具体案例

    这个 paragraph 通过 Frank Luntz 的 concrete example 来 illustrate 上一段提到的 political manipulation。Word use played a critical role 这个 topic sentence 直接 echoes 前文的 doubt campaign，然后 provide specific evidence：Luntz 建议用 climate change 因为它 sounded less scary。这是 典型的 exemplification pattern。

    这是 expository text 中的 evidence paragraph，它把 abstract claim（政治操纵）变成 concrete case study。通过 cite 具体人物和他的 memo，text 增强了 credibility 并 demonstrate 语言选择如何成为 political tool，这直接 support 主旨中 political manipulation 这一 dimension。

    举证操纵手法
  6. P6

    反驳政治影响论并揭示实际趋势

    这个 paragraph 通过 however 这个 adversative connector 来 challenge 前面的 political influence narrative。用 Google Ngram Viewer 的 data 证明 climate change 的 prevalence 其实 predates Luntz's recommendation，并且展示了 usage frequency 的 concrete trends，这是 data-driven refutation。

    这个 segment 展示了说明文的 complexity 和 nuance。它不是简单地 accept political manipulation narrative，而是 use empirical evidence 来 complicate the story，showing that usage patterns 有自己的 trajectory。这种 counter-evidence approach 增强了整篇文章的 credibility 和 objectivity。

    澄清使用趋势
  7. P7

    解释科学机构的术语选择

    这个简短的 paragraph 聚焦于 NASA's rationale for preferring climate change 这个 term。它 provide 一个 authoritative scientific perspective，explaining that this choice 是基于 accuracy consideration，因为 climate change better reflects the wide range of changes caused by greenhouse gases。

    这个 segment 回归到 scientific dimension，providing authoritative rationale for term preference。它 balances 前面关于 political manipulation 的 discussion，showing that scientific institutions 有自己的 legitimate reasons for term choice，这 reinforces 主旨中 clarifying distinctions 的部分。

    补充科学理据
  8. P8

    追溯历史渊源并总结现实共识

    这个 concluding paragraph 通过 a century ago 这个 time reference 把 discussion 追溯到 Svante Arrhenius 的 early debates，showing that这个 debate 有 long history。然后通过 now, of course 实现 temporal jump，最终 arrive at present consensus：不管 terminology 如何，human behavior is warming the planet with grave consequences。

    这是典型的 expository conclusion，它 perform double function：provide historical depth（追溯到 Arrhenius）来 contextualize 整个 debate，同时 deliver 一个 definitive statement about current scientific consensus。Whatever you call it 这个表达 elegantly circles back to 开篇的 terminology question，showing that underlying reality transcends terminology disputes。

    深化背景并总结
MAIN IDEA · 速判主旨

6 步定位这篇文章的主旨

不读完全篇也能锁定主旨——以下 6 步按2020年12月英语四级真题第3套 这篇原文的实际行文顺序给出，每步说明看哪里、看出什么，可直接迁移到其他英语四级文章。

  1. 首段问题定框架 P1

    说明文的 first paragraph 通常会 pose a question 或 introduce a topic 来 frame 整篇文章的 discussion focus,这为后续的 explanation 和 analysis 设定了 direction

  2. 时间轴串发展 P2 P3 P4 P5 P6

    说明文经常通过 tracing the history 或 evolution 来 explain concepts。本文用 chronological markers(1975, 1979, following decades)来 structure the explanation,这种 temporal progression 是 key indicator 表明文章在 explaining how something developed over time

  3. 对比词辨差异 P1 P3 P7

    本文的 core purpose 是 distinguish two terms,所以会出现大量的 comparison and contrast markers。像 'interchangeably'、'differences'、'more accurately'、'more broadly' 这些 words signal 文章在 making distinctions,这是判断主旨的 critical clue

  4. 权威源立可信 P2 P3 P5 P7 P8

    说明文为了 establish credibility 会 cite experts、institutions 或 organizations。本文提到 scientists、geochemist Wallace Broecker、National Academy of Sciences、NASA 等,这些 authoritative references 表明文章在 providing factual explanation rather than opinion,同时也 reveals 文章关注 scientific and institutional understanding

  5. 多维度全覆盖 P2 P3 P4 P5 P6 P7

    本文不仅讲 scientific origins,还涉及 political manipulation 和 public usage,这种 multi-dimensional coverage 表明文章主旨是 comprehensive explanation。说明文的主旨通常 encompasses all major aspects discussed,不会只 focus on single dimension

  6. 要素融合成主旨 P1 P2 P3 P4 P5 P6 P7 P8

    说明文的主旨是所有 key elements 的 synthesis。本文从 question about term differences 开始,通过 historical tracing 展示 evolution,用 contrastive analysis 说明 distinctions,引用 scientific and political sources 来 support explanation,覆盖 multiple dimensions。主旨必须 integrate 这些 components

主旨信号词 interchangeably P1 shaped P2 introduced P3 more broadly P3 sow doubt P4 played a critical role P5 more accurately P7 wide range of P7 Now, of course P8

MAIN IDEA · 主旨

这篇文章在说什么

这篇说明文解释了"全球变暖"和"气候变化"这两个术语的历史发展和区别,追溯了它们的科学起源、政治操纵和使用演变,同时阐明"气候变化"更准确地描述了人类活动对环境造成的更广泛影响。
This expository text explains the historical development and distinctions between the terms 'global warming' and 'climate change,' tracing their scientific origins, political manipulation, and evolving usage, while clarifying that 'climate change' more accurately describes the broader environmental impacts of human activities.
WORD INFERENCE · 生词推断

6 个生词的上下文推断

不查词典，只用文中线索推出词义——每个词给出推断出的释义与 完整推理链。已收录进英语四级高频真题词集的单词可点击进入词条页。

  • interchangeably 可互换地,可替代地

    现在我们将这些clues串联起来。首先,从morphology角度,inter- + change的组合指向'互相交换'这个core meaning。然后,第1段中的context显示两个terms被used in this manner,但随后的question challenges这种usage是否appropriate。这个logical flow告诉我们interchangeably描述的是一种将两者作为equivalents来使用、可以mutual substitution的方式。副词形式-ably确认了它是描述manner的adverb。所有evidence converge到同一个conclusion:这个词表达'可互换地、可替代地使用'的含义。

    三层剥离:词根搭配逻辑
  • geochemist 地球化学家

    将morphological和contextual clues结合,推理路径变得清晰:geo-明确指向earth或地球,chemist是化学家,所以geochemist就是研究地球化学的scientist。Context中Broecker研究climate change这个planetary phenomenon,further confirms这个专业focuses on Earth's chemical systems。两条线索相互reinforce,指向同一个precise definition。

    组分验证:词素加行为
  • acidification 酸化

    综合两条clues进行reasoning:morphologically,acid + -ification明确表示'变酸的过程'。Contextually,它是climate change导致的ocean environmental effect,与sea-level rise这类physical changes处于同一category。将这两个dimensions结合,可以confidently conclude acidification指的是海洋变酸这个chemical process,是global warming的一个specific consequence。

    词缀定性领域定向
  • deforestation 森林砍伐,毁林

    整合analysis的两个strands:从morphology角度,de- + forest明确指向removing forests;从context角度,它与fossil-fuel use同属于能够alter planetary climate的major human activities。这两条evidence线相互corroborate,指向一个unified conclusion:deforestation指的是砍伐、清除森林的行为,这是一种significant environmental destruction行为,能够contribute to climate change。

    前缀方向根词对象
  • memo 备忘录

    将两个layers的clues synthesize:syntactically,memo是一个可以be written的document,包含specific recommendations;contextually,它出现在professional strategic communication的setting中,由expert撰写并被媒体报道。这些features共同指向一个conclusion:memo是一种简短的、用于internal communication的written document,通常包含recommendations或information。结合professional context,可以推断这是备忘录或内部通知类文件。

    功能内容场景三维
  • greenhouse 温室

    整合两条reasoning paths:从word structure看,green + house的combination本身没有directly reveal其scientific meaning。但是通过第8段中对gases功能的description——trap heat——我们可以infer这个term来源于一个metaphor。某种能够let light in但trap heat的structure,这正是现实中greenhouse(温室)的working principle。因此greenhouse gases指的是在atmosphere中起到类似温室effect的gases,即温室气体。这个term体现了scientific naming中的analogical thinking。

    功能反推类比源
RHETORIC · 修辞手法

6 处修辞手法与仿写

每处修辞给出它在本文的具体用法、同类信号词清单与一份可直接套用的 写作仿写建议——读完能认，也能写。

  • 举例子

    P5

    作者通过 Frank Luntz 这个 specific example 来说明 political strategists 如何利用 word choice 来 influence public opinion。Luntz 建议使用 'climate change' 而非 'global warming'，因为前者 sounds less scary。这个 concrete case 有力地支撑了文章的 central argument：术语的使用不仅是 scientific 的，更是 political 的。Example 让 abstract concept 变得 tangible and credible，帮助 readers 理解语言如何被 weaponized 来 shape perception。

    信号词 For example For instance such as like including to illustrate as an illustration specifically in particular namely

    仿写： 写作时问自己：我的 general statement 需要什么样的 concrete proof？选择 examples 时要确保它们 representative and relevant。可以用 'For example' 或 'such as' 引入，然后提供 specific details（人名、数据、事件）。模版：[General statement]. For example, [specific person/case] [specific action/detail], which [shows/demonstrates/illustrates] [how it supports the main point]。

  • 引资料

    P3 P5 P6 P7

    文章多处 cite authoritative sources 来 establish credibility。第3段 引用了 geochemist Wallace Broecker 和 National Academy of Sciences report，为两个术语提供 historical and scientific origin。第5段 引用 the Guardian 的报道关于 Luntz's memo。第6段 使用 Google Ngram Viewer 的数据。这些 citations 不仅 validate 作者的 claims，更展示了 scientific rigor。通过 referencing credible sources，作者让 readers 相信这不是 personal opinion，而是 evidence-based analysis，这对说明文的 objectivity 至关重要。

    信号词 according to reported by published by stated in cited by as noted in research shows studies indicate experts suggest data from quoted in

    仿写： 写作时思考：哪些 claims 需要 external validation？选择 sources 时优先考虑 authoritative institutions, renowned experts, or peer-reviewed publications。引用时要 precise：提供 source name, date, 和 specific finding。模版：According to [source/expert], [quoted or paraphrased information]. 或 [Statement], reported/published by [source]. 记住要 integrate citations smoothly into your narrative，而非 awkwardly insert。

  • 列数字

    P3 P6

    第3段 提到 1975 和 1979 这两个 specific years，标记了术语出现的 precise timeline。第6段 提到 1993 和 'twice as often'，用 quantitative data 展示 usage frequency 的 change。这些 numbers 不是 decorative，而是 provide concrete evidence for temporal progression 和 usage trends。Numbers make the narrative precise and verifiable，让 readers 能够 track the evolution clearly。这种 numerical precision 增强了说明文的 scientific rigor。

    信号词 in [year] by [year] percent times twice number of ratio rate frequency approximately nearly

    仿写： 写作时问：哪些 statements 能用 numbers 来 strengthen？使用 specific figures 而非 general terms（'nearly twice' 比 'much more' 更 powerful）。Include dates 来 establish timeline，用 percentages 或 ratios 来 show comparisons。模版：In [year], [event/measurement]. 或 [Something] occurred [number] times more/less than [comparison]. 确保 numbers 是 accurate and sourced，并且 relevant to your point。

  • 下定义

    P3

    第3段 清晰地 define 了两个 key terms：'global warming' 被定义为 increases in Earth's average surface temperature，而 'climate change' 被定义为 the numerous effects of this increase。这个 precise definition 是整篇文章的 foundation，它 clarifies the distinction 并为后续 discussion 提供 conceptual framework。通过 authoritative definition from National Academy of Sciences，作者 establish 了 scientific basis for differentiating the terms，这直接服务于文章的 central purpose。

    信号词 is defined as refers to means is indicates describes term called known as definition in other words

    仿写： 写作定义时遵循 formula：[Term] + be动词 + category + distinguishing features。确保 definition 是 clear and concise，避免 circular definitions（用同一词来定义自己）。可以 contrast with similar terms 来 sharpen the distinction。模版：[Term] refers to/is defined as [essential characteristics], while [related term] refers to [different aspects]. 或者直接：[Term] means/is [clear explanation]。

  • 作比较

    P3 P5 P6

    文章的 entire structure 围绕 comparing 'global warming' 和 'climate change'。第6段 explicitly compares their usage frequency：'climate change was used nearly twice as often as global warming'。第5段 对比了两个术语的 perceived impact：'climate change' sounds less scary than 'global warming'。这种 systematic comparison 正是文章的 organizing principle，它帮助 readers understand not just what the terms mean，更重要的是 how they differ in usage, perception, and implications。Comparison makes abstract distinctions tangible。

    信号词 while whereas compared to in contrast on the other hand similarly unlike more than less than rather than but however

    仿写： 写作比较时选择 meaningful comparison points。Use comparative structures：'more...than', 'less...than', 'while...whereas'。可以 organize by point-by-point（逐点比较）或 block method（分块比较）。模版：[Item A] [characteristic], while [Item B] [contrasting characteristic]. 或 Compared to [Item A], [Item B] is [difference]. 确保 comparison 是 balanced and serves your explanatory purpose。

  • 作诠释

    P4 P7

    第7段 解释了 NASA 选择使用 'climate change' 的 rationale：'because it more accurately reflects the wide range of changes'。第4段 诠释了某些 industrialists and politicians 的 campaign purpose：'to sow doubt in the minds of the American public'。这些 explanatory statements 不仅 state facts，更 reveal underlying reasons and motivations。作诠释让 readers understand the 'why' behind the 'what'，deepening comprehension of complex issues beyond surface-level description。

    信号词 because since as the reason due to this means in other words that is which explains therefore thus reflects

    仿写： 写作诠释时 connect facts to their implications。Use explanatory phrases：'because', 'since', 'the reason is', 'this means'。先 present the fact，然后 explain its significance or cause。模版：[Fact/action] because [reason/explanation]. 或 This [phenomenon] reflects/indicates/shows [deeper meaning]. 确保 interpretation 是 logical and supported，而非 speculation。

IMPLIED MEANING · 言外之意

8 处话里有话

作者没有明说、但靠信号词传递出来的态度与暗示——每处给出原文片段、信号词类型与解读。

  • 看似互换实则有别

    P1
    seemingly interchangeably. But do they really mean the same thing?

    模糊限制语 seemingly apparently arguably supposedly presumably ostensibly on the surface

    Seemingly 这个 modifier 表面上说两个 terms 被 used interchangeably,但这个 hedge 本身就在 imply 这种 usage 可能是 inaccurate 的。紧跟的 rhetorical question 直接 challenge 了这个 common practice,为全文 establish 了 central mission:要 distinguish 这两个 terms。这个 opening gambit 对 main idea 的 value 在于它 immediately frames 文章为一篇 clarification text,告诉读者不要 assume 这两个 terms 是 synonymous,后续段落会 trace 它们的 distinct origins 和 evolving meanings。

  • 科学定义遭政治扭曲

    P2
    Scientists shaped the history of the terms while attempting to accurately describe... Later, political strategists adopted the terms to influence public opinion.

    时间对比类 Later Subsequently Eventually In time Afterwards Over time As time went on

    Later 这个 time marker 表面上只是 indicate chronological sequence,但它 implicitly establishes 一个 corruption narrative:科学家最初 shape 这些 terms 是为了 accuracy,但 political actors 后来 adopted 它们是为了 manipulate。这个 contrast 对 article's thesis 很 critical,因为它 explains 为什么 public 会 confused—不是因为 scientific definitions 本身 ambiguous,而是因为 terms 被 politically weaponized。这为后续 paragraphs 关于 Luntz 的 deliberate word choice 和 public confusion 的 discussion 做了 conceptual groundwork。

  • 术语并非对立而是包含

    P3
    global warming" to define increases in the Earth's average surface temperature, while "climate change" more broadly referred to the numerous effects

    对比类 while whereas in contrast on the other hand conversely by contrast alternatively

    While 这个 connector 表面上 presents two terms 并列,但 combined with "more broadly" 和 "numerous effects",它实际 establishes 一个 hierarchical relationship:global warming 是 specific phenomenon (temperature increase),climate change 是 comprehensive category (包括 warming plus other effects)。这个 subtle distinction 对 main thesis 至关重要,因为它 scientifically justifies 为什么 NASA 后来 prefer "climate change"—不是因为 political correctness,而是因为 terminological accuracy。这个 implication 在 第7段 得到 explicit confirmation。

  • 质疑运动的刻意性

    P4
    some industrialists and politicians launched a campaign to sow doubt in the minds of the American public

    情态词/动词搭配 launched a campaign to sow doubt launched a campaign to sought to undermine aimed to confuse worked to discredit attempted to obscure endeavored to mislead

    Launched a campaign to sow doubt 这个 phrasing 表面上 neutrally describes historical events,但 "sow doubt" 这个 metaphorical expression 有 strong negative implication—sowing 暗示 deliberate planting of something that will grow,doubt 在 scientific context 是 obstacle to truth。这 implicitly frames industrialists and politicians 为 bad actors who intentionally obscured scientific consensus。对 article's main idea 的 contribution 是它 explains 为什么 public 会 confused about terminology—不是因为 terms 本身 confusing,而是因为 vested interests actively manufactured confusion。这为 Luntz memo 的 discussion 提供 critical framing。

  • 措辞选择的心理操控

    P5
    encouraging the use of "climate change" because the phrase sounded less scary than "global warming"

    因果类/心理动机 because the phrase sounded less scary because...sounded less since...appeared more as...seemed softer given that...felt milder due to...came across as owing to...struck readers as

    Because...sounded less scary 这个 causal explanation 看似 neutral reporting Luntz's reasoning,但它 exposes 他的 recommendation 是 based on emotional manipulation 而非 terminological precision。"Sounded less scary" implies Luntz wasn't concerned with scientific accuracy,而是 concerned with reducing public alarm to benefit fossil fuel interests。这对 article's thesis 很 essential:它 demonstrates how political actors deliberately chose terms not for clarity but for emotional effect,further validating 为什么 scientific community prefers precise language。这个 exposure of manipulative motive 让 subsequent revelation (climate change was already more common) 更 ironic—Luntz's manipulation 其实 unnecessary。

  • 政治操纵实属徒劳

    P6
    However, Luntz's recommendation wasn't necessary. A Google Ngram Viewer chart shows that by 1993 climate change was already more commonly used

    转折类 However Nevertheless Yet Nonetheless Even so That said In spite of this

    However 这个 transition 看似 simply adding information,但它 fundamentally undercuts Luntz's memo 的 significance。"Wasn't necessary" combined with data showing "climate change" was already dominant in 1993 (before Luntz's work) creates powerful irony:political strategist thought 他 was shaping discourse,但 linguistic trend 早已 自然形成。这对 main thesis 的 value 是双重的:first,它 shows political manipulation 的 limits—language evolution 有 own momentum;second,它 suggests "climate change" 的 prevalence 不是 due to political spin,而是 due to its inherent suitability,为 NASA 的 scientific justification (第7段) 提供 stronger foundation。

  • 科学理由终胜政治

    P7
    NASA used the term "climate change" because it more accurately reflects the wide range of changes to the planet

    评价性比较 more accurately reflects better captures more precisely describes more faithfully represents more comprehensively covers more truly depicts more exactly conveys

    More accurately reflects 这个 phrase 看似 simply stating NASA's reasoning,但在 broader argumentative structure 里,它 provides definitive scientific answer to 第1段's opening question。对比 Luntz's emotion-based reason (less scary),NASA's accuracy-based rationale represents triumph of scientific precision over political spin。对 article's main thesis 的 crucial contribution 是它 resolves the terminology debate on scientific grounds:"climate change" 不是 politically motivated euphemism,而是 more comprehensive descriptor。这个 authoritative validation echoes 第3段's scientific distinction while implicitly refuting 第4段-5's political manipulations,bringing argumentative circle 完整。

  • 争议古已有之,共识终会达成

    P8
    Now, of course, we know that whatever you call it, human behavior is warming the planet, with grave consequences ahead

    时间对比类+确定性标记 Now, of course Today, naturally Currently, obviously At present, clearly Now, certainly Today, undoubtedly Nowadays, evidently

    Now, of course 这个 phrase pair 表面上 simply stating current knowledge,但它 performs two rhetorical functions:Now contrasts present certainty with 第8段's historical debates (Arrhenius's disagreements),showing science has progressed;of course presupposes reader acceptance,treating anthropogenic climate impact 为 established fact。"Whatever you call it" 这个 concessive clause 最终 resolves opening question—terminology matters for precision but不改变 underlying reality。对 main thesis 的 final contribution 是它 transcends terminology debate:无论 political manipulation or scientific precision,the physical fact remains。这个 closing move validates 全文 discussion of terms while asserting 更 fundamental truth,给 exposition 提供 both resolution and urgency (grave consequences)。

AUTHOR ATTITUDE · 作者态度

作者态度：客观中立

结论先行：本文作者态度为客观中立（ Objective and informative with subtle concern）。下面是按步骤还原的判断过程与文中的态度信号词。

  1. 问句开篇定中立基调 P1

    说明文中的 opening question 通常 signal 作者会采用 neutral tone 来 present information，因为 question 本身就是在 invite exploration 而非 impose judgment。这种 strategy 表明作者想 maintain objectivity。

  2. 时间线叙事体现客观性 P2 P3 P4 P5 P6 P7

    说明文作者如果 rely on chronological presentation 和 factual evidence (如这里的 1975、1979 等 specific dates)，通常表示他们想 maintain distance 并 let facts speak。这种 organizational pattern 是 objective attitude 的 key indicator。

  3. 多方观点呈现显平衡 P8

    说明文作者如果 give voice to various stakeholders 并用 neutral reporting language (如 'wrote a memo'、'used the term')，表明他们在 strive for fairness。但 concluding remarks 往往 reveal 作者的 true stance，这里的 'grave consequences' 是 subtle shift from pure objectivity。

  4. 信息占比主导态度归类 P1 P2 P3 P4 P5 P6 P7 P8

    综合来看，文章的 bulk 都在 presenting factual information without heavy modifiers，只在 very end 用了 'grave' 这个 slightly loaded term。这种 pattern 说明作者的 main intention 是 inform，而 concern 只是 implied rather than explicit，所以 overall attitude 仍属 objective category。

文中的态度信号词

  • seemingly interchangeably P1

    这个 phrase 中的 'seemingly' 表示作者在 question surface appearance，显示他想 dig deeper 而不是 accept 表面现象。这种 hedging language 是 objective writers 常用的，表明他们在 maintain critical distance。

    同类词 seemingly apparently ostensibly supposedly allegedly

  • accurately describe P2

    'Accurately' 这个 adverb 强调 scientists 追求 precision，而作者 adopt 这个 perspective 说明他也 value factual accuracy over persuasion。这种 language 反映作者的 commitment to truthfulness。

    同类词 accurately precisely objectively factually scientifically

  • introduced P3

    'Introduced' 是一个 neutral reporting verb，作者用它来 describe Broecker 的 action without adding judgment。这类 verbs 表明作者在 present facts 而非 interpret them with bias。

    同类词 defined reported stated published noted

  • launched a campaign to sow doubt P4

    这个 phrase 中的 'sow doubt' 带有 slightly negative connotation，暗示作者 disapprove 这种 behavior。但作者仍用 relatively neutral structure 'launched a campaign' 来 frame it，显示他在 maintain objectivity 的同时 subtly indicate 自己的 position。

    同类词 launched a campaign sow doubt attempted to influence sought to shape endeavored to affect

  • more accurately reflects P7

    'More accurately' 再次 emphasize precision，而作者 cite NASA 的 reasoning without challenge，说明他 align with 这种 emphasis on accuracy。这 reinforces 作者的 objective, fact-based approach。

    同类词 more accurately more precisely better represents more faithfully captures more appropriately describes

  • grave consequences P8

    'Grave' 是整篇文章中 strongest evaluative word，在 conclusion 出现表明作者的 underlying concern。虽然 overall tone 是 objective，但这个 word choice reveals 作者对 climate issue 的 worry，使 attitude 从 purely neutral 变为 neutral with concern。

    同类词 grave serious severe dire critical

GENRE · 速判体裁

30 秒判定这是一篇说明文

体裁决定读法与出题套路。以下判断步骤与标志词全部以本文为例，可直接迁移到其他英语四级 真题文章。

如何快速判断这是一篇说明文？

  1. 开篇提问引入概念 P1

    本文 第1段 直接 pose 了一个 question 关于两个 terms 的 difference，这是典型的 expository opening，aim 是 clarify concepts，而不是像 argumentative essay 那样 state a position，也不像 news report 那样 announce 一个 recent event with 5W elements。

  2. 时间线组织信息 P2 P3 P4 P5 P6 P7

    第2段 到 第7段 按照 historical timeline（1975→1979→following decades→1993→now）来 trace 这两个 terms 的 evolution，这是 chronological exposition。议论文会用 logical progression 来 build argument，新闻报道会把 most important information 放在 front。

  3. 客观陈述事实数据 P3 P4 P5 P6 P7 P8

    全文使用 neutral tone 来 present historical facts（如 第3段 的 dates and sources）、describe political tactics（第4段-5）、cite data（第6段 的 Google Ngram）和 explain scientific reasoning（第7段-8）。没有 strong evaluative language 或 urgent calls to action 来 persuade readers。

  4. 历史回溯总结解释 P8

    第8段 通过 historical context（Arrhenius 的 century-old debate）来 conclude 整个 explanation，最后用 'Now, of course, we know' 来 wrap up 对这个 terminology issue 的 clarification。这是 expository closure，不是 persuasive conclusion 也不是 news wrap-up。

  5. 整体交际目的是解释 P1 P2 P3 P4 P5 P6 P7 P8

    本文完全符合 expository genre 的 defining features：以 conceptual question 开篇，按 chronological order 展开 historical explanation，用 neutral register 呈现 facts and data，以 contextual summary 结尾。整体 communicative intent 是 clarify terminology confusion，不是 argue 某个 viewpoint 也不是 report 某个 event。

哪些词暴露了说明文体裁？

  • terms P1 说明对象定义解释词 mean define refer to called known as
  • history P2 说明顺序与例证词 shaped while attempting later during following
  • introduced P3 说明顺序与例证词 published report used referred to for example such as
  • define P3 说明对象定义解释词 referred to mean describe termed designated
  • numerous effects P3 事物属性功能描述词 effects influence impact consequences results
  • accurately describe P2 说明对象定义解释词 precisely explain clearly illustrate properly characterize correctly identify objectively present
  • because P7 说明顺序与例证词 since as due to owing to given that
  • debate P8 说明顺序与例证词 disagreed argued claimed discussion controversy
SENTENCE INSIGHTS · 句子精讲

10 句真题句逐层精讲

下列真题句各有独立的句子解析页——中文翻译、结构树逐层拆解、成分与时态、考点讲解与真题高频词。点击句子进入完整解析。

FAQ · 常见问题

关于 2020年12月英语四级真题第3套 Part III Section C (2) 的常见问题

2020年12月英语四级真题第3套 Part III Section C (2) 文章的主旨是什么？
2020年12月英语四级真题第3套 Part III Section C (2) 文章说明文解释了"全球变暖"和"气候变化"这两个术语的历史发展和区别,追溯了它们的科学起源、政治操纵和使用演变,同时阐明"气候变化"更准确地描述了人类活动对环境造成的更广泛影响。（英文表述：This expository text explains the historical development and distinctions between the terms 'global warming' and 'climate change,' tracing their scientific origins, political manipulation, and evolving usage, while clarifying that 'climate change' more accurately describes the broader environmental impacts of human activities.）
2020年12月英语四级真题第3套 Part III Section C (2) 文章是什么体裁？难度如何？
体裁为说明文，作者立场是客观中立（Objective and informative with subtle concern）。CEFR 难度 B2，全文 346 词、8 段；在英语四级全部 511 篇真题文章中，B2 级共 234 篇（占 46%）。
2020年12月英语四级真题第3套 Part III Section C (2) 文章的篇章结构是怎样的？
全文 8 段按说明文骨架分为 8 个意群：第1段——提出问题引发思考；第2段——概述术语演变的双重驱动力；第3段——追溯术语的科学起源；第4段——揭示政治操纵的开端；第5段——剖析语言操纵的具体案例；第6段——反驳政治影响论并揭示实际趋势；第7段——解释科学机构的术语选择；第8段——追溯历史渊源并总结现实共识。
2020年12月英语四级真题第3套 Part III Section C (2) 文章的作者态度是什么？
作者态度是客观中立（Objective and informative with subtle concern）。判断路径：问句开篇定中立基调 → 时间线叙事体现客观性 → 多方观点呈现显平衡 → 信息占比主导态度归类；文中的态度信号词包括 seemingly interchangeably（第1段）、accurately describe（第2段）、introduced（第3段）、launched a campaign to sow doubt（第4段）、more accurately reflects（第7段）、grave consequences（第8段）。
2020年12月英语四级真题第3套 Part III Section C (2) 文章中有哪些值得积累的生词？
按文中出现顺序共 6 个：interchangeably（可互换地,可替代地）、geochemist（地球化学家）、acidification（酸化）、deforestation（森林砍伐,毁林）、memo（备忘录）、greenhouse（温室），每个词的词义都可以由文中上下文线索推断得出。

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