懒笔记
2005年考研英语真题 Section I
Postgraduate · 来自 2005年考研英语真题 · Section I · 完形填空（四选一）

2005年考研英语真题 Section I

说明文 · 完形填空（四选一） · 真题文章逐层精读

本页是 2005年考研英语真题 Section I 文章的精读视角页——这篇说明文全文 280 词、3 段，CEFR 难度 C1（C1 级在考研英语文章中占 91%），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，其中能迁移到其他考研英语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

3 段英文原文

以下为2005年考研英语真题 Section I 的完形填空（四选一）原文，共 3 段。左侧 P1–P3 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 human nose is an underrated tool. Humans are often thought to be insensitive smellers compared with animals, but this is largely because, unlike animals, we stand upright. This means that our noses are limited to perceiving those smells which float through the air, missing the majority of smells which stick to surfaces. In fact, though, we are extremely sensitive to smells, even if we do not generally realize it. Our noses are capable of detecting human smells even when these are diluted to far below one part in one million.

Strangely, some people find that they can smell one type of flower but not another, whereas others are sensitive to the smells of both flowers. This may be because some people do not have the genes necessary to generate particular smell receptors in the nose. These receptors are the cells which sense smells and send messages to the brain. However, it has been found that even people insensitive to a certain smell at first can suddenly become sensitive to it when exposed to it often enough.

The explanation for insensitivity to smell seems to be that the brain finds it inefficient to keep all smell receptors working all the time but can create new receptors if necessary. This may also explain why we are not usually sensitive to our own smells – we simply do not need to be. We are not aware of the usual smell of our own house, but we notice new smells when we visit someone else's. The brain finds it best to keep smell receptors available for unfamiliar and emergency signals such as the smell of smoke, which might indicate the danger of fire.

PARAGRAPHS · 逐段精读

3 段逐段主旨与解读

逐段拆解2005年考研英语真题 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

    The Underestimated Sensitivity of the Human Nose

    Humans have a highly sensitive sense of smell, though upright posture limits the odors they can detect.

    本段承担全文的立论功能：它首先确立 human sense of smell 比通常认为的更敏锐这一总观点，并引出“为什么人类有时闻不到某些气味”的问题，为后两段讨论 genes 和 brain efficiency 铺垫。

    抓住转折后的纠偏结论
  2. P2

    Why Smell Sensitivity Varies Among People

    Genetic differences and repeated exposure influence people's sensitivity to particular smells.

    本段把首段“人类总体嗅觉灵敏”的宏观判断推进到个体层面：人们为什么会对某些味道敏感或迟钝。它既呼应文章主旨中的 genetic factors，也为下一段从 brain 如何调控 receptors 的更深层解释作了过渡。

    现象后合并双重影响
  3. P3

    The Brain's Efficient Prioritization of Smells

    The brain conserves smell sensitivity for unfamiliar or dangerous odors by reducing attention to familiar smells.

    本段是全文的深层解释与收束：它说明人类并非嗅觉迟钝，而是 brain 为了效率选择性地分配 smell receptors。该段完整落实文章主旨中 brain efficiency 的部分，并把嗅觉的价值提升到识别陌生信息和危险信号的生存功能。

    用熟悉气味反衬危险信号
SELF CHECK · 段落自检题

3 道逐段细节自检题

针对2005年考研英语真题这篇原文，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 insensitive smellers

    Why are humans often thought to be insensitive smellers compared with animals?

    • A Humans have fewer smell receptors than animals.
    • B Most smells in the air are too diluted for humans to detect.
    • C Their upright posture limits their noses mainly to smells carried through the air.
    • D Humans cannot perceive smells that float through the air.
    • E The human brain fails to process complex scent signals.
    • F Evolution has caused the human nose to become an underrated tool.
    显示答案与解析 收起答案与解析

    正确答案：C

    原文用 stand upright 解释人类鼻子的感知范围为何受到限制，并指出鼻子主要接收 float through the air 的气味。正确项以 upright posture 改写 stand upright，以 smells carried through the air 改写 smells which float through the air，保持了因果关系和范围限制。

    比较句后因果直取 直接用 insensitive smellers 在 第1段 定位比较句，再抓取其后紧邻的 because 和 unlike 所引出的原因。无需通读全部例证，只需核对选项能否改写该原因及其造成的感知限制，即可确定正确项。

  2. 第 2 段 定位词 exposed to it often enough

    According to the text, a person's inability to smell a certain flower can be changed by ________.

    • A altering the genetic structure of smell receptors.
    • B generating more messages to the brain.
    • C improving the sensitivity of all smell receptors.
    • D being exposed to it often enough
    • E learning to distinguish different flowers.
    • F avoiding the flower for a long period.
    显示答案与解析 收起答案与解析

    正确答案：D

    原文明确说明，起初对某种气味 insensitive 的人，在 exposed to it often enough 后也可能 become sensitive。正确项保留原文的 exposed 和 often enough，并用 being exposed 使其与题干中的 by 构成正确语法搭配。

    转折后条件直配 在 第2段 中先扫描 However，因为转折后常出现与前文状态不同的新信息。随后对照选项中的 exposure expression 与原文的完整条件，不必继续推测 genes 或 receptor function，即可确定正确项。

  3. 第 3 段 定位词 all smell receptors working all the time

    Why does the brain avoid keeping all smell receptors working all the time?

    • A Because our own smells are too strong to ignore.
    • B To avoid being distracted by familiar environments.
    • C The brain cannot process more than one smell at a time.
    • D Because smoke is the only emergency signal for the brain.
    • E To avoid inefficiency and keep receptors available for unfamiliar or emergency signals.
    • F New receptors can only be created during emergencies.
    显示答案与解析 收起答案与解析

    正确答案：E

    原文先指出让 all smell receptors 持续工作是 inefficient，随后说明大脑会让 receptors 可用于 unfamiliar and emergency signals。正确项把这两层明确依据合并：avoid inefficiency 对应机制评价，keep receptors available 对应功能用途，没有加入 energy consumption 等原文未说明的信息。

    低效判断与用途合并 利用完整短语在 第3段 首句定位后，只读取该句的机制评价以及后续说明 receptors 用途的句子。将这两条 evidence 合并，再排除含 only、cannot 或无依据心理目的的选项，即可快速确定正确项。

STRUCTURE · 篇章结构

3 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

    人类嗅觉的敏感性被低估

    这个 opening paragraph 首先 addresses 一个 common misconception，指出 humans 的 nose 其实是 underrated tool。作者通过 comparison with animals 来 explain，我们的 upright posture 限制了我们 perceive 那些 stick to surfaces 的 smells，但实际上我们对 airborne smells extremely sensitive，能 detect human smells 即使 diluted 到 far below one part in one million。这是典型的说明文 introduction，先 present 一个 counterintuitive fact 来 engage readers。

    这个 initial segment 直接 establishes 文章的 central claim，即 human sense of smell 比 commonly believed 更 sensitive。它通过 concrete evidence（dilution ratio）来 support 这个 assertion，为后续 paragraphs 关于 genetic factors 和 brain efficiency 的 explanation 奠定 foundation。在说明文中，这是 topic introduction 的典型功能。

    直接阐述嗅觉敏感性
  2. P2

    嗅觉差异的遗传因素

    这个 paragraph introduces 一个 interesting phenomenon：individual variations 在 smell perception 中。作者 describes 有些 people 能 smell one type of flower 但 not another，然后 provides genetic explanation，指出可能是因为缺少 necessary genes 来 generate particular smell receptors。这些 receptors 是 cells that sense smells 并 send messages to the brain。但作者也 mentions 一个 dynamic aspect：即使 initially insensitive 的人，通过 repeated exposure 也能 become sensitive。这是说明文中典型的 complication or exception pattern，adding nuance to the main claim。

    这个 sense group 对 main thesis 起到 elaboration 作用，specifically addressing 主旨中提到的 genetic factors。它 explains why 嗅觉 capabilities 会 be affected by 个体差异，通过 receptor generation mechanism 来 illustrate biological basis。同时，mentioning plasticity（exposure-induced sensitivity）adds complexity，showing 嗅觉不是 purely genetic 而是 somewhat adaptable。在说明文结构中，这是 supporting detail 层，为 central claim 提供 scientific explanation。

    解释遗传对嗅觉的影响
  3. P3

    大脑管理嗅觉受体的机制

    这个 concluding paragraph 提供了 deeper mechanistic explanation，focusing on brain's efficiency 在 managing smell receptors。作者 explains insensitivity to smell 的 underlying reason：brain 觉得 inefficient 让 all receptors work all the time，而是 can create new receptors if necessary。这也 accounts for 我们对 own smells 不 sensitive 的现象——simply don't need to be。文章用 concrete example（own house smell vs. new environment）来 illustrate，并 concludes with brain's strategy：prioritize unfamiliar and emergency signals 比如 smoke smell indicating fire danger。这是说明文的 synthesis 和 conclusion 部分，integrating previous points into overarching mechanism。

    这个 final sense group 对 thesis 起到 culminating explanation 作用，directly addressing 主旨中的 brain efficiency in managing smell receptors。它 synthesizes 前面的 observations（sensitivity, variation, adaptation）into unified theory：brain's resource management strategy。通过 explaining why we prioritize detecting new or dangerous odors over familiar ones，这个 segment 不仅 completes logical chain 还 provides practical implications。在说明文结构中，这是 deepest explanatory layer，revealing underlying principle that accounts for all previously described phenomena。

    阐释大脑效率机制
MAIN IDEA · 速判主旨

4 步定位这篇文章的主旨

不读完全篇也能锁定主旨——以下 4 步按2005年考研英语真题 这篇原文的实际行文顺序给出，每步说明看哪里、看出什么，可直接迁移到其他考研英语文章。

  1. 首段对比定主旨 P1

    说明文的 main idea 常常在首段就会 present 出来,尤其当作者要 challenge 一个 common misconception 时,会用 contrast structure 来凸显真实情况与大众认知的差异,这正是 topic 所在。

  2. 段落呼应验证法 P2 P3

    说明文的 structure 是 claim + support,如果后续段落都在 provide explanations、examples 或 mechanisms 来 support 首段观点,就证实了首段确实是 main idea。这种 coherence 是判断主旨的重要依据。

  3. 多因素归一法 P1 P2 P3

    当文章 present 了 multiple causes 或 contributing factors (如 genetic、physiological、evolutionary reasons) 来 explain 一个 central phenomenon 时,这些 factors 的 common target 就是文章主旨。说明文常用这种 multi-angle approach 来 comprehensive explain。

  4. 主张与因素整合法 P1 P2 P3

    说明文主旨不仅是 what (现象),还包括 why 和 how (原因和机制)。把首段的 overturned belief 和后续段落的 explanatory factors 结合起来,就得到了 comprehensive main idea,体现文章的 full scope。

主旨信号词 underrated P1 but P1 extremely sensitive P1 explanation P3 sensitive P1

MAIN IDEA · 主旨

这篇文章在说什么

人类的嗅觉比通常认为的更加灵敏。我们的嗅觉能力受到直立姿势、遗传因素以及大脑管理嗅觉感受器效率的影响,大脑会优先检测新的或危险的气味而非熟悉的气味。
The human sense of smell is more sensitive than commonly believed. Our olfactory capabilities are affected by upright posture, genetic factors, and brain efficiency in managing smell receptors, which prioritize detecting new or dangerous odors over familiar ones.
WORD INFERENCE · 生词推断

3 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。已收录进考研英语高频真题词集的单词可点击进入词条页。

  • underrated 被低估的;未被充分认识到价值的

    让我们把 clues 串起来:从 word formation 看,under- + rated 指向「评价不足」;从 discourse logic 看,作者说 nose 是 underrated tool,然后用 but 转折指出我们常被认为 smell 能力弱,最后又用 in fact 强调我们其实 extremely sensitive。这个 argumentative structure 清晰地表明:作者认为人类鼻子的 capability 被 underestimate 了。两条 clues converge 到同一个 meaning。

    前缀拆解+论证对比交叉验证
  • dilute 稀释;冲淡(使浓度降低)

    Integrate 两条 clues:从 quantitative description 看,one part in one million 是 extremely low ratio;从 concessive logic 看,even when 表示这是 challenging condition。作者的 point 是:即使在 smells 被 dilute 到如此低 concentration 的 extreme scenario 下,人类鼻子仍然 work。两条 clues 共同指向:dilute = reduce concentration to a very low level。

    数量表达揭示动作效果
  • receptor 受体;感受器(感知刺激并传递信号的细胞)

    让我们 synthesize:从 morphology 看,recept- + -or = receiver;从 explicit definition 看,它是 cells that sense and send messages;从 collocation patterns 看,它可以 work, be created, be kept available。三条 clues converge:receptor 是一种「接收装置」,specifically 是 biological cell,其 function 是 detect stimuli(这里是 smells)并 transmit signals to brain。这是 sensory system 的 fundamental component。

    词源+明确定义+功能动词三角验证
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。

  • 作比较

    P1

    第一段用 'compared with animals' 把人类的嗅觉与动物的嗅觉做对比，指出人类被普遍认为是 'insensitive smellers'，但随即用 'In fact' 反转，揭示这种 underestimate 并不成立——这个对比直接服务于文章主旨：人的嗅觉其实远比 commonly believed 更 sensitive。

    信号词 compared with in contrast to unlike whereas on the other hand by comparison similarly just as

    仿写： 试想：你要说明某事物被低估了，最有力的切入点是什么？可以先引出一个 widely held misconception，再用 'In fact' 或 'However' 做 turn，通过 contrast 打破偏见。仿写模版：'[A] is often thought to be [负面评价] compared with [B], but in fact, [A] is [正面事实], even when [具体条件].'

  • 列数字

    P1

    第一段末尾给出精确数据 'diluted to far below one part in one million'，用具体的 quantitative data 直接证明人类鼻子对 human smells 的 detection sensitivity 极高。这个数字把抽象的 'extremely sensitive' 变成了可量化的事实，有力支撑了主旨中 'more sensitive than commonly believed' 的核心论断。

    信号词 one part in one million as low as up to more than less than approximately nearly times as many as percent of

    仿写： 当你想说某事物'非常……'时，问自己：有没有一个 specific number 可以替换这个 vague adjective？哪怕是量级描述（如 'one in a million'）也远比 'very'、'extremely' 更有说服力。仿写模版：'[说明对象] is so [特征] that it can [动作] even when [条件] to as low/high as [具体数字/比例].'

  • 举例子

    P2

    第二段用 'some people find that they can smell one type of flower but not another' 这个具体的 scenario 来举例说明 smell sensitivity 因人而异的现象，使抽象的 'genetic differences in smell receptors' 变得 vivid 且 relatable，帮助读者理解 genetic factors 如何影响嗅觉能力——这与主旨中 'affected by genetic factors' 直接呼应。

    信号词 for example for instance such as take … as an example consider the case of some people find that a case in point is to illustrate

    仿写： 当你需要说明一个抽象规律时，问自己：在日常生活中有没有一个人人都能 relate to 的 concrete scene？找到之后，先描述这个 scene，再用 'This is because' 或 'This may be due to' 引出 underlying mechanism。仿写模版：'Some [people/things] find that they can [A] but not [B], whereas others [C both]. This may be because [抽象机制解释].'

  • 下定义

    P2

    第二段用 'These receptors are the cells which sense smells and send messages to the brain' 对 'smell receptors' 这一专业术语给出精确的 definition，解释其 biological function。这个 definition 是理解后续 brain efficiency 论述的 prerequisite，服务于主旨中 'brain efficiency in managing smell receptors' 的说明。

    信号词 is defined as refers to is known as is a … that are the … which means can be described as is the process by which

    仿写： 在说明文中引入专业术语时，立刻问自己：读者是否已经知道这个词的含义？如果不确定，就用 'X is/are + [类别] + that/which + [功能/特征]' 的句式给出 definition，让读者和你站在同一个 conceptual starting point 上。仿写模版：'[术语] are the [上位类别] which [核心功能], enabling [更大的系统/过程].'

  • 作诠释

    P2 P3

    第三段开头用 'the brain finds it inefficient to keep all smell receptors working all the time but can create new receptors if necessary' 对第二段末尾提到的 'people can suddenly become sensitive after repeated exposure' 这一现象给出 mechanistic explanation，进一步阐释其背后的 brain efficiency logic，深化了主旨中 'brain efficiency in managing smell receptors' 的核心论断。

    信号词 the explanation for … is that this is because this may be because the reason why … is that this accounts for hence therefore as a result this suggests that

    仿写： 当你描述一个现象后，读者可能会问 'Why does this happen?'——作诠释就是预判并回答这个问题。可以用 'The explanation for … seems to be that …' 或 'This may be because …' 引出。仿写模版：'The explanation for [现象] seems to be that [机制]. This may also explain why [延伸现象], since [逻辑推导].'

  • 举例子

    P3

    第三段用 'We are not aware of the usual smell of our own house, but we notice new smells when we visit someone else's' 这个极其 relatable 的日常 scenario，以及 'the smell of smoke, which might indicate the danger of fire' 这一 emergency example，来具体说明 brain 优先保留 smell receptors 用于 unfamiliar 和 emergency signals 的 efficiency principle，使抽象的 brain management logic 变得 tangible，有力支撑了主旨中 'prioritize detecting new or dangerous odors' 的论点。

    信号词 for example for instance such as take … as an example consider the case of a clear example is to illustrate like

    仿写： 注意这里作者连用两个 examples（一个 everyday scenario，一个 emergency scenario），形成 escalation effect，从 mundane 到 life-critical，说服力层层递进。仿写时可以刻意设计这种 from ordinary to extreme 的 example pairing。仿写模版：'We are not [aware/sensitive] to [熟悉事物], but we immediately notice [新事物/危险事物]. A clear example of this priority is [紧急信号], which might indicate [潜在危险].'

IMPLIED MEANING · 言外之意

4 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。

  • 人类嗅觉实际上很灵敏

    P1
    Humans are often thought to be insensitive smellers compared with animals, but this is largely because, unlike animals, we stand upright.

    转折类 but however yet nevertheless nonetheless although though

    这个 implication 是在告诉 readers：虽然 people commonly believe 人类的 sense of smell 不如动物敏锐，但这个 belief 其实是 misleading 的。真正的 reason 不是我们的 olfactory capability 差，而是我们的 upright posture 限制了我们能 detect 的 smells 范围。这个 implied meaning 对文章 main idea 非常 crucial，因为它 sets up 整篇文章的 foundation：人类嗅觉其实 underrated，我们需要 re-evaluate 对它的 understanding。它为后续 paragraphs 关于 smell sensitivity 和 receptor functionality 的讨论 paves the way。

  • 嗅觉不敏感可以改变

    P2
    However, it has been found that even people insensitive to a certain smell at first can suddenly become sensitive to it when exposed to it often enough.

    转折类 However however but yet nevertheless still even so

    这里的 implication 是：即使某人 initially 对某种 smell 不敏感，这种 insensitivity 不是 permanent 的。通过 repeated exposure，大脑可以 develop 相应的 receptors。这个 implied message 对文章 thesis 很重要，因为它 demonstrates 人类 olfactory system 的 flexibility 和 adaptability。它 supports 文章的 main point，即人类的 sense of smell 比我们 typically assume 的更加 sophisticated and capable。这也为第三段关于 brain efficiency 的 explanation 做了 foreshadowing。

  • 大脑选择性管理嗅觉受体

    P3
    the brain finds it inefficient to keep all smell receptors working all the time but can create new receptors if necessary

    委婉表达 inefficient not optimal less practical unnecessary redundant not economical wasteful

    这个 implied meaning 是：大脑采取的是一种 resource management strategy。与其 maintain 所有 smell receptors in active state（这样会 consume 大量 neural resources），大脑选择 selective activation，只 keep receptors for potentially important smells like smoke（danger signals）。这个 implication 对文章 main thesis 至关重要，因为它 explains 为什么我们对 familiar smells 不敏感（比如 our own house smell），而对 novel 或者 threatening smells 保持 alert。这 reveals 人类 olfactory system 的 intelligent design，supporting 文章的 overall argument that our sense of smell is more sophisticated than commonly appreciated。

  • 我们对自身气味不敏感有其必要性

    P3
    This may also explain why we are not usually sensitive to our own smells – we simply do not need to be.

    模糊限制语 simply do not need to be simply just merely only not really not particularly

    这里的 implication 深刻：我们对 our own smells 的 insensitivity 不是 deficiency，而是 strategic allocation of cognitive resources。如果我们 constantly aware of our own smell，这些 familiar information 会 occupy 宝贵的 neural capacity，prevent 我们 detecting truly important smells（比如 smoke indicating fire）。这个 implied message reinforces 文章的 central thesis：人类 olfactory system 是 highly efficient 和 purpose-driven 的。它 demonstrates 我们的 sense of smell 不是 inferior，而是 optimized for survival and adaptation。这 concludes 文章对 human nose 从 underrated 到 properly understood 的 reframing。

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（ objectively informative with corrective intent）。下面是按步骤还原的判断过程与文中的态度信号词。

  1. 识别开篇纠正性词汇 P1

    在 expository writing 说明文中，opening stance 开篇立场往往 set the tone 定下基调。用 underrated 表明作者认为某个 ability 能力被 underestimate 低估了，这是一种 corrective but neutral 纠正性但中立的 attitude 态度，不是 emotional criticism 情绪化批判，而是 factual correction 事实纠正。

  2. 统计事实证据密度 P1 P2 P3

    说明文的 neutral attitude 中立态度主要体现在 evidence-based reasoning 基于证据的推理上。作者没有用 I think、I believe 这类 subjective markers 主观标记，而是用 in fact、it has been found、the explanation seems to be 这些 objective reporting phrases 客观陈述短语。这种 approach 方法表明作者在 inform rather than persuade 告知而非说服。

  3. 追踪解释性连接词 P2 P3

    说明文的 core mission 核心使命是 clarify and explain 阐明和解释。当作者 consistently use 持续使用 explanatory frameworks 解释性框架（because、therefore、this means that），而不是 persuasive tactics 说服策略（we must、it's essential、clearly superior），就表明 attitude 态度是 informative rather than evaluative 信息性而非评价性的。

  4. 综合多维度信号 P1 P2 P3

    说明文的 neutral objectivity 中立客观性通过 absence of bias markers 缺乏偏见标记来 manifest 体现：没有 extreme adjectives 极端形容词，没有 personal pronouns in opinion contexts 观点语境中的人称代词，没有 emotionally charged vocabulary 情感化词汇。作者只是 present what is 呈现事实，不 advocate what should be 倡导应当如何。

文中的态度信号词

  • underrated P1

    Underrated 这个词 establish 确立了作者的 corrective stance 纠正性立场，表明作者认为 human nose 人类鼻子的 ability 能力被 unfairly judged 不公平地评判了。但注意这不是 angry criticism 愤怒批判，而是 mild correction 温和纠正，保持 objective tone 客观语气。

    同类词 underestimated overlooked underappreciated undervalued dismissed

  • in fact P1

    In fact 这个 phrase 短语是 classic marker 经典标记，表示作者在 present factual correction 呈现事实性纠正。它 signal 标志着从 common belief 普遍认知到 actual truth 实际真相的 transition 转变，强化了 objective informative purpose 客观信息目的。

    同类词 actually in reality as a matter of fact indeed it turns out

  • seems to be P3

    Seems to be 这类 hedging language 模糊限制语 demonstrate 展示了作者的 cautious approach 谨慎态度。作者没有 make absolute claims 做出绝对断言，而是 present tentative explanations 呈现试探性解释，这是 scientific objectivity 科学客观性的 hallmark 标志。

    同类词 appears to may be might be could be is likely

  • strangely P2

    Strangely 这个词 highlight 突出了一个 unusual phenomenon 不寻常现象，但注意它不是 judgmental 评判性的，而是 observational 观察性的。作者用它来 draw attention 引起注意，保持 curious rather than critical 好奇而非批判的 tone 语气。

    同类词 interestingly surprisingly curiously remarkably notably

  • it has been found P2

    It has been found 这个 phrase 短语是 scientific reporting 科学报告的 standard expression 标准表达，表明作者在 cite research evidence 引用研究证据而非 personal opinion 个人观点。这强化了 objective informative stance 客观信息性立场。

    同类词 research shows studies indicate evidence suggests findings reveal data demonstrate

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，可直接迁移到其他考研英语 真题文章。

如何快速判断这是一篇说明文？

  1. 开篇句的动词类型 P1

    说明文的 core purpose 是 explain how or why something works，议论文是 persuade readers 接受某个 argument，新闻报道是 inform readers 关于 recent events。Opening sentence 直接揭示了 the human nose 这个 object 和它的 characteristics，是典型的 explanatory approach。

  2. 段落间的递进关系 P1 P2 P3

    第1段 presents 一个 phenomenon（humans are sensitive smellers），第2段 explores 一个 specific aspect（individual differences in smell sensitivity），第3段 provides 一个 scientific explanation（brain mechanism）。这是典型的 progressive exposition，不是 back-and-forth debate。

  3. 表达的客观性标记 P1 P2 P3

    文章用 'in fact'、'it has been found that'、'the explanation seems to be' 等 neutral expressions 来 present information，没有 'we must'、'it is crucial' 等 persuasive language，也没有 'according to'、'yesterday' 等 news reporting markers。

  4. 三维特征的交叉验证 P1 P2 P3

    这篇文章完美符合 expository pattern：开篇 define human nose 的 capability，中间 explore individual differences 和 underlying reasons，结尾 explain brain mechanism，整体是 knowledge transmission 而非 opinion expression 或 event reporting。

哪些词暴露了说明文体裁？

  • is P1 事物属性定义词 are refers to means represents constitutes
  • In fact P1 事实强化标记词 Actually Indeed As a matter of fact In reality The fact is
  • This means that P1 说明顺序推论词 This indicates This suggests Therefore As a result Consequently
  • are capable of P1 事物功能描述词 can are able to have the ability to function to serve to
  • This may be because P2 原因解释标记词 The reason is This is due to This is caused by This occurs because The explanation is
  • These receptors are P2 专业术语定义词 are the cells which refers to is defined as is known as is called
  • However, it has been found that P2 研究发现引入词 it has been found that research shows studies indicate experiments reveal evidence suggests
  • The explanation for P3 显性解释引导词 The reason for The cause of What explains This is explained by This can be explained by
  • may also explain why P3 推理延伸标记词 might account for could be why this suggests that this may indicate this potentially explains
  • such as P3 举例说明标记词 for example for instance like including e.g.
SENTENCE INSIGHTS · 句子精讲

5 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 2005年考研英语真题 Section I 的常见问题

2005年考研英语真题 Section I 文章的主旨是什么？
人类的嗅觉比通常认为的更加灵敏。我们的嗅觉能力受到直立姿势、遗传因素以及大脑管理嗅觉感受器效率的影响,大脑会优先检测新的或危险的气味而非熟悉的气味。（英文表述：The human sense of smell is more sensitive than commonly believed. Our olfactory capabilities are affected by upright posture, genetic factors, and brain efficiency in managing smell receptors, which prioritize detecting new or dangerous odors over familiar ones.）
2005年考研英语真题 Section I 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（objectively informative with corrective intent）。CEFR 难度 C1，全文 280 词、3 段；在考研英语全部 70 篇真题文章中，C1 级共 64 篇（占 91%）。
2005年考研英语真题 Section I 文章的篇章结构是怎样的？
全文 3 段按说明文骨架分为 3 个意群：第1段——人类嗅觉的敏感性被低估；第2段——嗅觉差异的遗传因素；第3段——大脑管理嗅觉受体的机制。
2005年考研英语真题 Section I 文章的作者态度是什么？
作者态度是客观中立（objectively informative with corrective intent）。判断路径：识别开篇纠正性词汇 → 统计事实证据密度 → 追踪解释性连接词 → 综合多维度信号；文中的态度信号词包括 underrated（第1段）、in fact（第1段）、seems to be（第3段）、strangely（第2段）、it has been found（第2段）。
2005年考研英语真题 Section I 文章中有哪些值得积累的生词？
按文中出现顺序共 3 个：underrated（被低估的;未被充分认识到价值的）、dilute（稀释;冲淡(使浓度降低)）、receptor（受体;感受器(感知刺激并传递信号的细胞)），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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