作者：圣才电子书
出版社：圣才电子书
格式: AZW3, DOCX, EPUB, MOBI, PDF, TXT
2019年新托福阅读理解高分特训100篇【命题分析＋答题攻略＋强化训练】试读：
第1章 新托福（TOEFL iBT）阅读考试指南
1.1 新托福（TOEFL iBT）简介
TOEFL（Test of English as a Foreign Language，简称托福），由美国教育考试服务中心（ETS, Educational Testing Service）这一美国最大的考试机构在全世界举办，是一项旨在针对申请到美国或加拿大等国家上大学或读研究生的母语非英语的人进行的英语水平考试。
TOEFL是受到广泛认可的学术英语测试之一，130个国家中的6000多所大专院校和机构承认托福成绩，所以考生的托福成绩可在世界范围内得到认可。托福考试也是最方便报考的英语考试之一，考生可在180个国家中超过4500个考试中心报名参加托福考试。
新托福考试（TOEFL iBT）从2005年9月起在美国开始启动，之后在世界各地的考试中心举办。新托福考试（iBT，即以互联网为依托）取代了以计算机为依托的托福考试（CBT）。对于无法进行新托福考试的地区，考生仍可参加纸笔形式的托福考试（PBT）。
新托福考试的四部分包括了阅读、听力、口语、写作等语言运用的各种技能，侧重考查考生在学术环境中有效使用英语的能力，利用综合性试题，反映真实的学术环境。TOEFL iBT能够反映学生在一流大专院校的教学和校园生活中的语言应用能力。全部考试约三个半小时，听力测试结束后有10分钟的休息时间。
新托福的考试构成：
1.2 新托福（TOEFL iBT）阅读考试命题规律
新托福考试阅读部分主要考查考生阅读和理解文章的能力。新托福考试阅读由3～5篇长度为每篇700单词左右的文章构成。考生有20分钟来阅读每篇文章并回答问题。阅读部分的时间一共有60（如果考3篇文章）分钟或100分钟（如果考5篇文章）。屏幕上有一个时钟，提示考生阅读部分所剩的时间。
◆出题形式
阅读部分有两种形式。在稍短的一种中，考生将阅读3篇文章；在稍长的一种中，考生将阅读5篇文章。每篇文章后面有12～14道题。
如果只有3篇短文，那么每篇文章都将计入成绩；如果有5篇文章，只有3篇文章计入成绩，另外2篇是试验性题目，不计人总分，仅为以后考试提供参考。但考生不知道哪些是试验性题目，所以必须尽力答好每一道题。
阅读时可以记笔记，并可以利用笔记来答题，但笔记不记分。有些短文中会有带下划线的词或词组，点击之后会出现相关的定义或解释。
◆题目类型
根据ETS的《新托福考试官方指南》，新托福阅读部分考查的题目类型包括：事实信息题、否定排除题、指代题、词汇题、推断题、修饰目的题、简化句子题、插入文本题、文章总结题、完成图表题。除了文章总结题和完成图表题以外，每道题的分值都是1分。文章总结题的分值可能是2分，完成图表题为3或4分。在完成一套试题后，考生可以使用复查功能查找没有回答的题目。
◆真实体验
阅读部分分成几个部分。点击“Next”可移至下一问题；点击“Back”可返回上一问题。在同一阅读部分中，考生可返回到前面任意一篇文章的任意一个题目，但考生开始下一部分的阅读后，将不能返回到上一部分阅读的题目。在点击“Next”至下一部分的阅读前，确认你已经完成本部分中的所有题目。
点击“Review”后可以看见一张列表，标明了各部分短文中已完成和未完成的问题。考生可以从这个界面回到当前部分中未完成的题目。
◆考查内容
阅读考试将考查考生对文章主旨、重要信息、词汇和文中各观点之间关系的分析和理解能力。其具体要求为：
确定文章主要观点并辨别主要观点和次要观点；
辨别所给信息正确与否，还缺哪些信息；
判断文中所使用的词汇和短语的正确意思；
推断出文中没有直接给出的信息；
判定作者的写作目的；
理解句与句之间的关系；
从文中所给信息总结并组织文章的重要观点。
1.3 新托福（TOEFL iBT）阅读考试文章类型
新托福阅读理解题的文章大多取材于国外大学的教科书，一般不做任何修改，从而能够更好地被用于评估考生在学术英语氛围下的阅读能力。其内容主要是说明、讨论或解释各类学科中的基本概念、现象、理论、方法和研究等。
◆文章题材
从文章的内容类别来看，生物科学的内容占30%，自然科学的内容占30%，社会人文的内容占20%，其他内容占20%，这些内容一般会是学生在大学第一年和第二年学习过程中经常遇到的话题。所用文字通常不是很随意或口语化，而是比较正式、学术性的文字。
◆文章体裁
文体一般可分为说明（exposition）、议论（argumentation）和史实（historical）三类，而架构则常常会表现为分类（classification）、比较（comparison/contrast）、因果（cause/effect）、解疑（problem/solution）四种之一。所有的问题都出自原文，考生无需该学科领域的专业知识即可完成题目。
1.4 新托福（TOEFL iBT）阅读考试十大题型讲解
根据美国ETS发行的《新托福考试官方指南》，在新托福阅读考试中共有十种题型，我们在此将会对这十种题型一一进行详细的介绍，并指出解题攻略。希望备考的考生们能通过讲解，对于托福阅读考试有一个准确的把握。
新托福阅读具体题型如下：
1. 事实信息题（Factual Information Questions）
2. 否定事实信息题（Negative Factual Information Questions）
3. 词汇题（Vocabulary Questions）
4. 指代题（Reference Questions）
5. 推断题（Inference Questions）
6. 修辞目的题（Rhetorical Purpose Questions）
7. 简化句子题（Sentence Simplification Questions）
8. 插人文本题（Insert Text Questions）
9. 文章总结题（Prose Summary）
10. 完成图表题（Fill in a Table）
其中，前八种为微观题，解题不需要联系文章主旨。后两种为宏观题，解题需要联系文章主旨，其难度高于微观题。
新托福阅读考试的十种题型有六种是沿用旧托福考试中已经出现的题型（事实信息题、否定事实信息题、推断题、修辞目的题、词汇题、指代题），而四种新题型，句子简化题、插入文本题、文章总结题和图表题，代表了托福考试的新动向，是需要引起广大考生的重视的。下面我们就来对这十种题型一一进行讲解。
1. 事实信息题（Factual Information Questions）
●题型介绍
事实信息题其实就是我们熟悉的细节题，这种类型的题的要求是选择和文章内容相一致的部分。这是托福阅读考试中可能占到最大比重的一种题型，主要考查的是提取关键词和在文章中定位有用解题信息的能力。
●答题策略
回答事实信息题的时候，最重要的能力就是快速找到与问题相关的内容，然后迅速找出和所给内容一致的答案。所以解答这部分题的基本策略是：首先，确定问题相关内容之后，找出问题中的关键词；然后，回到原文中精准地找到解题的关键句子；最后能够进行熟练的转述表达（paraphrasing）。
2. 否定事实信息题（Negative Factual Information Questions）
●题型介绍
否定事实信息题其实就是我们熟悉的排除题，这类题型很好识别，一般就是在题干中会出现一个大写的单词EXCEPT、NOT、LESS。这类问题出现的频率较高，但其中一般是对一段内容而不是全文的信息的考查。
●答题策略
否定事实信息题中，因为各种信息都比较分散，可以采用逐个比较排除的方法，这样相对来说时间会花费得多些。现在ETS为了提高托福阅读的考试难度，所采用的一种方法就是在文章中增加否定信息题的出现频率。
3. 词汇题（Vocabulary Questions）
●题型介绍
词汇题主要是进行同义词的转换，每篇文章都会出3～5个词汇问题，相当于全部问题的1/3。词汇题考查的主要是典型的托福用词汇、具有多义的基本词汇和词组表达。
●答题策略
为了在词汇题上取得高分，增加词汇量非常重要，深度理解基本词汇也很必要。对于初考者来说，记忆大量的托福词汇是个很好的办法，对于高级英语学习者来说，在理解基本词汇的基础上加以应用是很有帮助的。其基本的解题策略是：理解词语和短语的意思；联系上下文进行解答。
4. 指代题（Reference Questions）
●题型介绍
文章中的指示代词所指的对象，既可以是单独的名词和代词，也可以说句子、文章等等。由于指代题难度不高，现在在托福考试中出现的概率不是很高。
●答题策略
解答指代题的关键是理解理解指示词的意义，找出指示词所指代的内容。指示词不是固定的，它可能是之前出现过的单词或句子。所以其中关键的步骤是仔细查看指示词所在的句子或者其前面的句子。
5. 推断题（Inference Questions）
●题型介绍
推断题最关键的本质就是作者强烈暗示，最常考的就是否定关系和比较关系的推理。如果问题中出现动词infer的话，就很容易知道是推断题。这一类型的问题会出现0～3个。
●答题策略
推断题的解题难度要略高于事实信息题，因为考生不仅要理解原文的意思，还要据此来做一步逻辑上的推理。推断题的一般解题策略是根据所给内容进行一定范围内的猜想，所以需要快速找出根据内容，然后通过适当的思考得出结论。
6. 修辞目的题（Rhetorical Purpose Questions）
●题型介绍
修辞目的题需要考生掌握隐藏在文中的作者意图，探知特定位置出现特定内容的原因，想要把握这个问题就需要跟随文章的整体脉络了解部分内容与周围句子的关系。
这种类型的题根据题目需要考虑段落整体的结构和重心或前后句的修饰逻辑，其考查重点是段落结构与句间关系。平均每篇阅读有0～2道题。
●答题策略
解答这类题的基本思路是：1）判断命题方向，上下文结构抑或是观点与举例；2）阅读全句或简读段落指定部分，把握前后句或多句叙述逻辑及基本关系；3）据前后句修饰或段内各句间逻辑关系对选项进行选择。
7. 简化句子题（Sentence Simplification Questions）
●题型介绍
简化句子题考查学生能否选择出正确的句子来改写标出来的核心内容（essential information）。每篇文章平均出现一道这样的题。
●答题策略
解答这类题的基本思路是：首先要梳理所给文章的结构，找出核心内容，然后用更加简洁的表达方式来进行重述（restatement）。其正确答案的特点是：1）一般与原句结构基本一致；2）包含原句所有基本信息。
8. 插人文本题（Insert Text Questions）
●题型介绍
插入文本题考查的是考生是否具备从文章中找出逻辑顺序的能力。其题目设置一般为把文章中的某一部分取出来设置成4个选项，然后让考生选出可以让文章流畅的正确答案。每篇短文都平均有一道这样的问题，一般放在倒数第二道题。
●答题策略
解答这类题的基本思路是：1）读插入句，根据关键字和要点和句子逻辑关系来选择。其中关键字一般是逻辑连词，代词和关键成分。2）回到原文，明确文章论述顺序及结构；3）选出正确答案，对文章段落的逻辑结构进行再确认。
9. 文章总结题（Prose Summary）
●题型介绍
文章总结题主要是找出整篇文章的核心内容，然后进行缩写。题目中给出第一句，再加上6道选项，选出3项符合文章大意的正确选项。每篇文章平均会有一道这样的题型。
●答题策略
解答这类题的基本思路是：1）选出正确答案，对文章段落的逻辑结构进行再确认；2）结合文章结构，对选项进行甄别；3）通常错误选项是细节或与论述的主题无关。
10. 完成图表题（Fill in a Table）
●题型介绍
文章中对两个以上的对象进行对比或分类时，出现图表题的概率比较大。有两种出题形式，分别为选项有9个选项和7个选项。得分情况为有9个选项时选对7个得4分，有7个选项时选对5个得3分，少选一个正确选项减1分。因此想得1分以上的话，不管哪种情况都至少要选对选项的一半以上。图表题和总结题一般都出现在最后一题。
●答题策略
解答这类题的基本策略是：1）通常错误选项是细节或与论述的主题无关；2）阅读选项；把握选项中的关键词；3）以文章结构为参照，按关键词定位选项，对选项的点进行排除。
1.5 新托福（TOEFL iBT）阅读方法
新托福考试特别强调考生的阅读速度，要提高阅读速度，正确的阅读方法是解决问题的关键。下面我们介绍一些正确的阅读方法。
1. 扫读
扫读（scanning）是指以最快的速度扫视所读材料，在找到所需信息时才仔细阅读该项内容。如查找原因、例子、事情起因、作用或者事物特点等，也即在寻找特定信息、寻找具体事实、寻找答题所需内容时都用得着这种方法。
2. 略读
略读(skimming)是指选择性地阅读。通常的阅读要求看到每一个词，每次注目看1～2个词。而略读对眼睛跳动的频率和幅度的要求较高，不需要看清每一个词，有时甚至从上一行跳到下一行。略读不可能使读者全部了解文章内容，但能大大地提高阅读速度，也能获得大量的信息。
略读(skimming)的作用在于对文章主题和文章结构有一个基本了解。略读过程中，重点阅读首段的前两句或前三句和此后每一段的第一句话。一定要注意文中反复出现的关键单词和词组。
3. 研读
研读（study reading）就是指仔细阅读，通过这种阅读可以对文章有透彻深刻的理解。根据考题，运用上下文、逻辑关系、背景知识进行判断和推论。对难句的理解和推理以及一些事实性细节题需要用这种方法。
4. 滚动浏览
滚动浏览(scrolling)就是利用电脑的滚动条在屏幕上迅速移动文章。当文章太长、无法同时看到全文的时候，考生必须要通过滚动文章来浏览全文。考生无论是略读文章纵览全文，还是浏览段落寻找细节，滚动浏览都是非常重要的一项辅助技能。
1.6 新托福（TOEFL iBT）阅读评分标准
新托福的阅读考试评分标准如下：
第2章 新托福（TOEFL iBT）基础阅读篇
2.1 生物科学类（Passage 1～6）
Passage 1 题材：Zoology 字数：631The Origin of Cetacean
[1] It should be obvious that cetaceans whales, porpoises, and dolphins-are mammals. They breathe through lungs, not through gills, and give birth to live young. Their streamlined bodies, the absence of hind legs, and the presence of a fluke and blowhole cannot disguise their affinities with land dwelling mammals. However, unlike the cases of sea otters and pinnipeds (seals, sea lions, and walruses, whose limbs are functional both on land and at sea), it is not easy to envision what the first whales looked like. Extinct but already fully marine cetaceans are known from the fossil record. How was the gap between a walking mammal and a swimming whale bridged? Missing until recently were fossils clearly intermediate, or transitional, between land mammals and cetaceans.
[2] Very exciting discoveries have finally allowed scientists to reconstruct the most likely origins of cetaceans. In 1979, a team looking for fossils in northern Pakistan found what proved to be the oldest fossil whale. The fossil was officially named Pakicetus in honor of the country where the discovery was made. Pakicetus was found embedded in rocks formed from river deposits that were 52 million years old. The river that formed these deposits was actually not far from an ancient ocean known as the Tethys Sea.
[3] The fossil consists of a complete skull of an archaeocyte, an extinct group of ancestors of modem cetaceans. Although limited to a skull, the Pakicetus fossil provides precious details on the origins of cetaceans. The skull is cetacean-like but its jawbones lack the enlarged space that is filled with fat or oil and used for receiving underwater sound in modern whales. Pakicetus probably detected sound through the ear opening as in land mammals. The skull also lacks a blowhole, another cetacean adaptation for diving. Other features, however, show experts that Pakicetus is a transitional form between a group of extinct flesh-eating mammals, the mesonychids, and cetaceans. It has been suggested that Pakicetus fed on fish in shallow water and was not yet adapted for life in the open ocean. It probably bred and gave birth on land.
[4] Another major discovery was made in Egypt in 1989. Several skeletons of another early whale, Basilosaurus, were found in sediments left by the Tethys Sea and now exposed in the Sahara desert. This whale lived around 40 million years ago, 12 million years after Pakicetus. Many incomplete skeletons were found but they included, for the first time in an archaeocyte, a complete hind leg that features a foot with three tiny toes. Such legs would have been far too small to have supported the 50-foot-long Basilosaurus on land. Basilosaurus was undoubtedly a fully marine whale with possibly nonfunctional, or vestigial, hind legs.
[5] An even more exciting find was reported in 1994, also from Pakistan. The now extinct whale Ambulocetus natans (“the walking whale that swam”) lived in the Tethys Sea 49 million years ago. It lived around 3 million years after Pakicetus but 9 million before Basilosaurus. The fossil luckily includes a good portion of the hind legs. The legs were strong and ended in long feet very much like those of a modern pinniped. The legs were certainly functional both on land and at sea. The whale retained a tail and lacked a fluke, the major means of locomotion in modern cetaceans. The structure of the backbone shows, however, that Ambulocetus swam like modern whales by moving the rear portion its body up and down, even though a fluke was missing. The large hind legs were used for propulsion in water. On land, where it probably bred and gave birth, Ambulocetus may have moved around very much like a modern sea lion. It was undoubtedly a whale that linked life on land with life at sea.
1. In paragraph 1, what does the author say about the presence of a blowhole in cetaceans?
A. It clearly indicates that cetaceans are mammals.
B. It cannot conceal the fact that cetaceans are mammals.
C. It is the main difference between cetaceans and land-dwelling mammals.
D. It cannot yield clues about the origins of cetaceans.
2. Which of the following can be inferred from paragraph 1 about early sea otters?
A. It is not difficult to imagine what they looked like.
B. There were a great number of them.
C. They lived in the sea only.
D. They did not leave many fossil remains.
3. The word precious in the passage is closest in meaning to _____.
A. exact
B. scarce
C. valuable
D. initial
4. Pakicetus and modern cetaceans have similar _____.
A. hearing structures
B. adaptations for diving
C. skull shapes
D. breeding locations
5. The word it in the passage refers to _____.
A. Pakicetus
B. fish
C. life
D. ocean
6. The word exposed in the passage is closest in meaning to _____.
A. explained
B. visible
C. identified
D. located
7. The hind leg of Basilosaurus was a significant find because it showed that Basilosaurus _____.
A. lived later than Ambulocetus natans
B. lived at the same time as Pakicetus
C. was able to swim well
D. could not have walked on land
8. It can be inferred that Basilosaurus bred and gave birth in the following locations: _____.
A. On land
B. Both on land and at sea
C. In shallow water
D. In a marine environment
9. Why does the author use the word luckily in mentioning that the Ambulocetus natans fossil included hind legs?
A. Fossil legs of early whales are a rare find.
B. The legs provided important information about the evolution of cetaceans.
C. The discovery allowed scientists to reconstruct a complete skeleton of the whale.
D. Until that time, only the front legs of early whales had been discovered.
10. Which of the sentences below best expresses the essential information in the underlined sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
A. Even though Ambulocetus swam by moving its body up and down, it did not have a backbone.
B. The backbone of Ambulocetus, which allowed it to swim, provides evidence of its missing fluke.
C. Although Ambulocetus had no fluke, its backbone structure shows that it swam like modem whales.
D. By moving the rear parts of their bodies up and down, modem whales swim in a different way from the way Ambulocetus swam.
11. The word propulsion in the passage is closest in meaning to _____.
A. staying afloat
B. changing direction
C. decreasing weight
D. moving forward
12. Look at the four squares,,,, and that show where the following sentence could be inserted in the passage. Where could the sentence be best added?
This is a question that has puzzled scientists for ages. Their streamlined bodies, the absence of hind legs, and the presence of a fluke and blowhole cannot disguise their affinities with land dwelling mammals. However, unlike the cases of sea otters and pinnipeds (seals, sea lions, and walruses, whose limbs are functional both on land and at sea), it is not easy to envision what the first whales looked like. Extinct but already fully marine cetaceans are known from the fossil record. How was the gap between a walking mammal and a swimming whale bridged? Missing until recently were fossils clearly intermediate, or transitional, between land mammals and cetaceans.
13. Directions: An introduction for a short summary of the passage appears below. Complete the summary by selecting the THREE answer choices that mention the most important points in the passage. Some sentences do not belong in the summary because they express ideas that are not included in the passage or are minor points from the passage. This question is worth 2 points.
This passage discusses fossils that help to explain the likely origins of cetaceans, whales, porpoises, and dolphins.
●
●
●Answer Choices
A. Recent discoveries of fossils have helped to show the link between land mammals and cetaceans.
B. The discovery of Ambulocetus natans provided evidence for a whale that lived both on land and at sea.
C. The skeleton of Basilosaurus was found in what had been the Tethys Sea, an area rich in fossil evidence.
D. Pakicetus is the oldest fossil whale yet to be found.
E. Fossils thought to be transitional forms between walking mammals and swimming whales were found.
F. Ambulocetus’ hind legs were used for propulsion in the water.【文章大意】
本文主要介绍的是能够清晰表现鲸鱼在从陆生哺乳动物到海生哺乳动物过渡时期的化石。1979年，一个小组在巴基斯坦北部地区找到了被证明是最古老的鲸鱼的化石。另一个重大发现发生于1989年的埃及，几块龙王鲸（另一种早期鲸鱼）的骨骼被发现于特提斯海遗留下的沉积物中，现在在撒哈拉沙漠暴露出来。一个更令人激动的发现是在1994年报道的，也来自巴基斯坦，已灭绝的走鲸（“会游泳的走动鲸鱼”）生活在四千九百万年前的特提斯海洋。它生活在Pakicetus之后约三百万年的时期，但是比龙王鲸早九百万年。【答案详解】
1. B 细节题。根据文章第一段第三句话“the presence of a fluke and blowhole cannot disguise their affinities with land dwelling mammals.”可知，气孔（blowhole）不能掩盖它们与陆栖哺乳动物有密切关系这一事实。故答案为B项。
2. A 推断题。根据第一段中间部分“unlike the cases of sea otters and pinnipeds ... it is not easy to envision what the first whales looked like”可知，还原海獭（sea otter）的原貌并不困难，但是还原鲸鱼的原貌不容易，故答案为A项。
3. C 词汇题。precious意为“宝贵的，珍贵的”，选项中只有valuable与其同义。故答案为C项。
4. C 细节题。文章第三段详细描述了Pakicetus（巴基鲸）and modern cetaceans（现代鲸鱼）之间的异同。根据第三句话“The skull is cetacean-like but ...”可以推断出，巴基鲸和现代鲸鱼的颅骨（skull shape）相似。故答案为C项。
5. A 文章第三段最后提到了巴基鲸（Pakicetus）的生活习性，而代词it指代的正是本段一直在描述的Pakicetus，故答案为A项。
6. B 词汇题。expose意为“暴露，揭露”。选项中只有B项visible最符合expose的词义，故答案为B项。
7. D 细节题。根据文章第四段倒数第二、三句可知，龙王鲸（Basilosaurus）的后腿（hind leg）脚掌只有3个脚趾头。这样的小脚支撑不了50英尺长的 Basilosaurus的陆地生活。故答案为D项。
8. D 推断题。根据文中第四段最后一句对Basilosaurus（龙王鲸）的描述可以得知，龙王鲸完全是一种海生的动物，由此可以推断出它会在海里繁殖。故答案为D项。
9. B 推论题。由于在陆地鲸化石中发现了后腿（hind leg），科学家们从中获得了更多有关陆地鲸的重要和完整的信息。故答案为B项。
10. C 原句提供了四个信息“the structure of the backbone”；“Ambulocetus swam like modern whales”；“the rear portion of its body；a fluke was missing”。C项通过句型转换对原句重新作出了解释，并完整地表达了原句的语义，故答案为C项。
11. D 词汇题。根据构词法，前缀pro-表示“往前”，pulse意为“跳动”，由此可以推测出，propulsion应该有“往前跳动，往前推动”的含义。故D项为正确答案。
12. D 解答本题的关键在于本段的设问句“How was the gap between a walking mammal and a swimming whale bridged?”除了这个设问句，其他句子描述的都是细节状况，而所要求插入的句子不仅可以作为该设问句的答语，同时也是一个主题句，使句与句之间的语义更加连贯。因此，插入D处最为恰当。
13. ABE 本题考查的的是主题句与例证句之间逻辑关系的分析能力。本主题句包含了两个重要信息“fossils”和“origins of cetaceans-whales，porpoises, and dolphin ...”。A项是对第一个主题信息的扩展，近期的化石发现有助于了解陆地哺乳动物和鲸类动物之间的密切联系。B项是对第二个主题信息的补充，Ambulocetus的发现为证明鲸鱼曾经在陆地和海洋中都生活过提供了证据。E项对二个主题信息的进一步说明，被认为是陆地行走的哺乳动物和水生鲸鱼的过渡期形式的化石被找到了。其他选项与主题无关，故答案为ABE。【词汇装备】
cetacean n. 鲸鱼
mammal n. [脊椎] 哺乳动物
streamlined adj. 流线型的
disguise vt. 掩饰；假装；隐瞒
envision vt. 想象；预想
intermediate adj. 中间的，中级的
embed vt. 使嵌入，使插入
skull n. 头盖骨
transitional adj. 变迁的；过渡期的
nonfunctional adj. 无功能的
vestigial adj. 退化的；残余的；发育不全的
extinct adj. 灭绝的，绝种的
locomotion n. 运动；移动
propulsion n. 推进；推进力
undoubtedly adv. 确实地，无庸置疑地
Passage 2 题材：Neurology 字数：623THE SENSE OF SMELL
[1] Smell is the most direct of all the senses. It is thought to be the oldest sense in terms of human evolution, which may explain why smell is hard-wired into the brain. The olfactory nerve, which manages the perception of smells, is essentially an extension of the brain. The olfactory nerve provides a direct link from receptors at the top of the nose to the portion of the brain that controls memory, emotion, and behavior.
[2] The olfactory system detects certain airborne chemicals that enter the nose and then transmits this chemical information to the limbic system in the brain. The olfactory region at the upper end of each nostril is yellow, moist, and full of fatty substances. The shade of yellow indicates the strength of the sense of smell: the deeper the shade, the keener and more acute it is. Animals have a very strong sense of smell, so their olfactory regions are dark yellow to reddish brown, while those of humans are light yellow.
[3] When an odorous substance enters the nose, it binds to olfactory receptor cells, the neurons lining the yellow upper portion of the nasal cavity. Olfactory receptor cells contain microscopic hairs called cilia that extend into the layer of mucus coating the inside of the nose. Odor molecules diffuse into this region and are absorbed by the cilia of the olfactory receptor cells. What this means is that when we hold a rose to our nose and inhale, odor molecules float up into the nasal cavity, where they are absorbed by five million olfactory receptor cells. The receptor cells alert the olfactory nerve, which sends impulses to the brain’s olfactory bulb, or smell center. Thus, olfactory information about the rose enters the brain’s limbic system, where, in most of us, it stimulates a feeling of pleasure.
[4] The limbic system of the brain integrates memory, emotion, and behavior. The system is composed of a group of related nervous system structures that are the functional center of emotions such as anger, fear, pleasure, and sadness. The components of the limbic system are linked to the cerebral cortex, the part of the brain involved in complex learning, reasoning, and personality. The cerebral cortex makes decisions about the emotional content of these unique human qualities after “consulting” the limbic system and other brain centers in processing and retrieving memories. It may, in turn, use memories to modify behavior.
[5] Scent may be the strongest trigger of memory and emotions. When we inhale a scent, receptors in the brain’s limbic center compare the odor entering our nose to odors stored in our memory. Along the way, memories associated with those odors are stimulated. A smell can be overwhelmingly nostalgic because it triggers powerful images and emotions. The waxy fragrance of crayons can instantly transport us to our second-grade classroom, or the scent of freshly mown grass can flood us with the joy of summer freedom. What we see and hear may fade quickly in short-term memory, but what we smell is sent directly to long-term memory.
[6] Smells can increase alertness and stimulate learning and retention. In one study, children memorized a word list, which was presented both with and without accompanying scents. The children recalled words on the list more easily and with higher accuracy when the list was given with scents than without, showing the link between smell and the ability to retain information. In another study, researchers examined how various smells can increase alertness and decrease stress. They found that the scent of lavender could wake up the metabolism and make people more alert. They also found that the smell of spiced apples could reduce blood pressure and avert a panic attack in people under stress.
Glossary
nostalgic: causing a desire for things, persons, or situations of the past; causing homesickness
retention: the act of retaining; keeping, holding, or maintaining
1. Why does the author use the term hard-wired in describing the sense of smell and the brain?
A. To describe the texture and feel of the olfactory nerve.
B. To emphasize the close connection between smell and the brain.
C. To compare the power of smell with that of other senses.
D. To explain how the sense of smell evolved in early humans.
试读结束[说明：试读内容隐藏了图片]