一、做題技巧

List of headings 這類題目設(shè)置的要求可以簡(jiǎn)單的概括為給原文中的段落找最為合適的段落大意。既然是給段落找段落大意。所以，正確答案往往是原文內(nèi)容的概括或是改寫。和其他類型的客觀題一樣，用詞和原文高度一致的選項(xiàng)都不會(huì)是正確答案。如果所有答案都是原文的照抄，那么，考察學(xué)生的就不是英語能力，而是"大家來找茬"的能力了。我們就以Cambridge IELTS 7 test 3 Passage 2 (P69)的一篇文章為例給大家講解Lisf of headings的做題技巧。

Question 14-19

Lisf of headings

I the results of the research into blood-variants

ii Dental evidence

iii Greenberg`s analysis of the dental and linguistic evidence

iv Developments in the methods used to study early population movements

v Indian migration from Canada to U.S.A

vi Further genetic evidence relating to the three-wave theory

vii Long-standing questions about prehistoric migration to America

viii Conflicting views of the three wave theory ,based on non-genetic evidence

ix Questsions about the causes of the prehistoric migration to America

x How analysis of blood-variants measures the closeness of the relationship between different populations

14 section A

15 section B

16 section C

17 section D

18 section E

19 section F

Example Answer

20 section G vii

Population movements and genetics

A Study of the origins and distribution of human populations used to be based on archaeological and fossil evidence. A number of techniques developed since the 1950s, however, have placed the study of these subjects on a sounder and more objective footing. The best information on early population movements is now being obtained from the 'archaeology of the living body', the clues to be found in genetic material.

B Recent work on the problem of when people first entered the Americas is an example of the value of these new techniques. North-east Asia and Siberia have long been accepted as the launching ground for the first human colonizers of the New World. But was there one major wave of migration across the Bering Strait into the Americas, or several？ And when did this event, or events, take place？ In recent years, new clues have come from research into genetics, including the distribution of genetic markers in modern Native Americans.

C An important project, led by the biological anthropologist Robert Williams, focused on the variants (called Gm allotypes) of one particular protein - immunoglobin G- found in the fluid portion of human blood. All proteins 'drift', or produce variants, over the generations, and members of an interbreeding human population will share a set of such variants. Thus, by comparing the Gm allotypes of two different populations (e.g. two Indian tribes), one can establish their genetic 'distance', which itself can be calibrated to give an indication of the length of time since these populations last interbred.

D Williams and his colleagues sampled the blood of over 5,000 American Indians in western North America during a twenty- year period. They found that their Gm allotypes could be divided into two groups, one of which also corresponded to the genetic typing of Central and South American Indians. Other tests showed that the Inuit (or Eskimo) and Aleut formed a third group. From this evidence it was deduced that there had been three major waves of migration across the Bering Strait. The first, Paleo-lndian, wave more than 15,000 years ago was ancestral to all Central and South American Indians. The second wave, about 14,000-12,000 years ago, brought Na-Dene hunters, ancestors of the Navajo and Apache (who only migrated south from Canada about 600 or 700 years ago). The third wave, perhaps 10,000 or 9,000 years ago, saw the migration from North-east Asia of groups ancestral to the modern Eskimo and Aleut.

E How far does other research support these conclusions Geneticist Douglas Wallace has studied mitochondrial DNA in blood samples from three widely separated Native American groups: Pima- Papago Indians in Arizona, Maya Indians on the Yucatan peninsula, Mexico, and Ticuna Indians in the Upper Amazon region of Brazil. As would have been predicted by Robert Williams's work, all three groups appear to be descended from the same ancestral (Paleo-lndian) population.

F There are two other kinds of research that have thrown some light on the origins of the Native American population; they involve the study of teeth and of languages. The biological anthropologist Christy Turner is an expert in the analysis of changing physical characteristics in human teeth. He argues that tooth crowns and roots have a high genetic component, minimally affected by environmental and other factors. Studies carried out by Turner of many thousands of New and Old World specimens, both ancient and modern, suggest that the majority of prehistoric Americans are linked to Northern Asian populations by crown and root traits such as incisor shoveling (a scooping out on one or both surfaces of the tooth), single-rooted upper first premolars6 and triple-rooted lower first molars.

According to Turner, this ties in with the idea of a single Paleo-lndian migration out of North Asia, which he sets at before 14,000 years ago by calibrating rates of dental micro-evolution. Tooth analyses also suggest that there were two later migrations of Na-Denes and Eskimo- Aleut.

G The linguist Joseph Greenberg has, since the 1950s, argued that all Native American languages belong to a single 'Amerind' family, except for Na-Dene and Eskimo-Aleut - a view that gives credence to the idea of three main migrations. Greenberg is in a minority among fellow linguists, most of whom favour the notion of a great many waves of migration to account for the more than 1,000 languages spoken at one time by American Indians. But there is no doubt that the new genetic and dental evidence provides strong backing for Greenberg's view. Dates given for the migrations should nevertheless be treated with caution, except where supported by hard archaeological evidence. section F

經(jīng)過多年的實(shí)踐和反饋，一般比較推薦大家采取先看文章標(biāo)題，再看選項(xiàng)，再看文章段落，再比較文章和選項(xiàng)，最終選出答案的順序。值得提醒的是，list of headings與其他雅思閱讀題目不同，這類題型的練習(xí)題的位置在文章的前面。也就是每道list of headings所對(duì)應(yīng)的文章都在題目的后面。如果找錯(cuò)了對(duì)應(yīng)的文章不但會(huì)使考生無法解題更會(huì)浪費(fèi)大量考試時(shí)間。

首先大家需要看的是文章的標(biāo)題。標(biāo)題是對(duì)文章高度的概括，可以幫助大家在短時(shí)間內(nèi)快速了解文章的大意。本文的標(biāo)題為Population movements and genetics， 大家對(duì)于genetics可能相對(duì)不太熟悉，genetics的意思為遺傳學(xué)。對(duì)于閱讀中遇到的較為生疏的單詞，詞匯基礎(chǔ)較好的同學(xué)可以采取詞根詞綴法，對(duì)于詞匯基礎(chǔ)較為薄弱的可以采用聯(lián)想法。例如genetics這個(gè)單詞的前一半是gene，大家可以很快的聯(lián)想到這個(gè)詞和中文中"基因"的發(fā)音很像。很快可以想到這個(gè)詞和基因會(huì)有一定關(guān)系，也就能大致猜出單詞的意思了。

對(duì)于選項(xiàng)的信息處理往往會(huì)決定考生是否可以很順利的完成本套試題。 此類題型在考察中往往會(huì)給考生們一個(gè)或多個(gè)例子，也就是說其中有一道題或者多道題目的答案是已經(jīng)選好的。本類題目中每個(gè)答案都只會(huì)使用一次。所以考生在做題中的第一步就是應(yīng)該劃掉其中已經(jīng)給出答案的題目。在本題中，首先需要做的事情就是確定20題所對(duì)應(yīng)的VII選項(xiàng)和文章的G段在本題中是不要重點(diǎn)閱讀的部分。但是值得提醒考生的是，一般在整套閱讀試卷中l(wèi)ist of headings 題目不考察的段落往往會(huì)在其他題目中考察，以盡量擴(kuò)大考生的閱讀量。

接下來，在閱讀選項(xiàng)中大家需要將選項(xiàng)中的關(guān)鍵詞適當(dāng)畫出并且識(shí)別出選項(xiàng)中的一些特定成分。我們就以此題為例,給大家一一分析。首先，如果大家縱覽選項(xiàng)會(huì)發(fā)現(xiàn)，其中有些選項(xiàng)是很類似的，例如II Dental evidence 和iii Greenberg`s analysis of the dental and linguistic evidence 以及vii Long-standing questions about prehistoric migration to America 和ix Questions about the causes of the prehistoric migration to America。 考生可以有這樣的經(jīng)驗(yàn)，在本類題目中一般相類似的選項(xiàng)上都會(huì)有一個(gè)是對(duì)的。根據(jù)以往的經(jīng)驗(yàn)，這兩個(gè)相似的選項(xiàng)中較為概括的一個(gè)，成為正確選項(xiàng)的可能性往往更大一些。

其次，為了便于閱讀文章后檢索答案，考生需要在閱讀試題時(shí)將試題中題干的主體部分重要信息做出標(biāo)示。同時(shí)根據(jù)list of headings題目的設(shè)置原則，有些選項(xiàng)中出現(xiàn)的特定內(nèi)容也會(huì)給考生一些很重要的線索。List of headings 這類題目設(shè)置的要求是給原文中的段落找最為合適的段落大意。那么選項(xiàng)中的一些過于具體的信息，例如：人名，地名，時(shí)間等肯定信息不應(yīng)該出現(xiàn)在正確選項(xiàng)中，除非整篇文章的主題就是某人、某地、某物。如Cambridge IELTS 5 P64頁 的 the disappearing delta中首段中正確答案包含Egypt這一地名，但是由于全文都是在說發(fā)生在Egypt的事情，所以也就可以接受了。同時(shí)，由于是概括大意，不同于其他細(xì)節(jié)類題，例TURE/FALSE/NOT GIVEN，需要精確到某一個(gè)單詞，本題的最終答案只是段落代號(hào)，只需要精確到段落。所以選項(xiàng)中如果包含了很好定位的詞也不太可能是正確答案。試想一下，如果每個(gè)選項(xiàng)都可以輕易地定位到某一段，考生只需要在做題時(shí)根據(jù)題目的定位詞就可以確定文章中哪一段是答案，那么題目就過于簡(jiǎn)單了。所以大家可以根據(jù)這個(gè)原則，將題目中有具體信息的選項(xiàng)優(yōu)先排除，本題中的III V VII IX四個(gè)選項(xiàng)都因?yàn)檫€有較為明顯的地名而大大降低了候選的概率。但考慮到VII IX都較為類似，同時(shí)排除的可能性不大。對(duì)于一般選項(xiàng)，考生可以將選項(xiàng)中的核心詞稍作記號(hào)，一般優(yōu)先考慮非標(biāo)題含有名詞，其次是形容詞。

接下來，考生需要做的就是對(duì)文章的分析。雅思閱讀文章的長(zhǎng)度大約在850-1200字之間，大多數(shù)的考生無法將整篇文章全部認(rèn)真讀完。考生可以根據(jù)學(xué)術(shù)寫作的文章結(jié)構(gòu)有的放矢的閱讀。學(xué)術(shù)文章的段落結(jié)構(gòu)較為固定，一般為：topic sentence（ main idea） -reasons-facts(example and evidence)的結(jié)構(gòu)。所以，考生如果希望在短時(shí)間內(nèi)快速找到文章的段落大意，文章中的首句、第二句、末句是需要重點(diǎn)閱讀的。之所以還需要閱讀第二句是因?yàn)椴糠治恼轮袝?huì)在第一句topic sentence的后邊加上一句轉(zhuǎn)折，較為常見的標(biāo)志有But Yet However. 極少的文章會(huì)將主題句放在最后一句中，一般會(huì)出現(xiàn)總結(jié)、轉(zhuǎn)折詞，例如：But So Thus 所以部分文章需要看最后一句。 除此之外，段落中一些特殊符號(hào)也是值得大家關(guān)注的，最為常見的特殊符號(hào)為：?jiǎn)柼?hào)，冒號(hào)，破折號(hào)。

二、例題分析

我們就以本篇文章為例，選取其中具有代表性的題目給大家一一分析。

B Recent work on the problem of when people first entered the Americas is an example of the value of these new techniques. North-east Asia and Siberia have long been accepted as the launching ground for the first human colonisers of the New World. But was there one major wave of migration across the Bering Strait into the Americas, or several？ And when did this event, or events, take place？ In recent years, new clues have come from research into genetics, including the distribution of genetic markers in modern Native Americans.

VII Long-standing questions about prehistoric migration to America

Ix Questions about the causes of the prehistoric migration to America

大家會(huì)發(fā)現(xiàn)文章B段的第一句話讀完之后并不能幫助我們解題?？忌约佑^察就會(huì)發(fā)現(xiàn)在本段的后半部分有兩個(gè)很明顯的問句。很顯然，能夠很好的概括問句的詞就是 questions.但是文章中關(guān)于questions的選項(xiàng)有VII 和IX兩個(gè)。對(duì)于相似的選項(xiàng)大家可以通過進(jìn)一步的比較找出區(qū)別。在這兩個(gè)選項(xiàng)中，VII選項(xiàng)中包含了long-standing長(zhǎng)期遺留的，而IX選項(xiàng)中有核心詞 causes。仔細(xì)閱讀文章中兩個(gè)問句考生會(huì)發(fā)現(xiàn)原文并沒有提及任何的原因。所以答案很顯然是VII。

C An important project, led by the biological anthropologist Robert Williams, focused on the variants (called Gm allotypes) of one particular protein - immuneoglobin G- found in the fluid portion of human blood. All proteins 'drift', or produce variants, over the generations, and members of an interbreeding human population will share a set of such variants. Thus, by comparing the Gm allotypes of two different populations (e.g. two Indian tribes), one can establish their genetic 'distance', which itself can be calibrated to give an indication of the length of time since these populations last interbred.

x How analysis of blood-variants measures the closeness of the relationship between different

Sectionｃ中涉及的C落段落結(jié)構(gòu)較為特殊。考生們很快會(huì)發(fā)現(xiàn)在文章的最后部分出現(xiàn)了thus這一表示總結(jié)的單詞，那么這句話會(huì)是閱讀的重點(diǎn)部分。最后一句話詞匯難度較高，很多同學(xué)會(huì)很難讀懂。在看不懂原文句子的具體意思時(shí)，大家可以采取尋找替換詞的方式解題。例如本段的后半部和X選項(xiàng)中出現(xiàn)了 closeness和distance， relationship 和populations last interbred這對(duì)同意替換詞。 那么答案選X也就順理成章了。

E How far does other research support these conclusions Geneticist Douglas Wallace has studied mitochondrial DNA in blood samples from three widely separated Native American groups: Pima- Papago Indians in Arizona, Maya Indians on the Yucatan peninsula, Mexico, and Ticuna Indians in the Upper Amazon region of Brazil. As would have been predicted by Robert Williams's work, all three groups appear to be descended from the same ancestral (Paleo-lndian) population.

F There are two other kinds of research that have thrown some light on the origins of the Native American population; they involve the study of teeth and of languages. The biological anthropologist Christy Turner is an expert in the analysis of changing physical characteristics in human teeth. He argues that tooth crowns and roots have a high genetic component, minimally affected by environmental and other factors. Studies carried out by Turner of many thousands of New and Old World specimens, both ancient and modern, suggest that the majority of prehistoric Americans are linked to Northern Asian populations by crown and root traits such as incisor shoveling (a scooping out on one or both surfaces of the tooth), single-rooted upper first premolars6 and triple-rooted lower first molars.

ii Dental evidence

iii Greenberg`s analysis of the dental and linguistic evidence

section E 的解法也類似，paragraph E 中開頭就是一個(gè)問句。在考試中遇到問句，考生需要把問句本身和回答問句的句子一并仔細(xì)閱讀。 這兩句話和vi選項(xiàng)分別有 further和 how far does other，genetic evidence 和 DNA 兩對(duì)同義替換詞?？忌谶@種情況下可以很肯定的選擇Vi。 section F的題目設(shè)計(jì)較新也比較狡猾。大家通過閱讀F段可以很快找到文章的前兩句話中與III選項(xiàng)中分別有l(wèi)anguage和linguistics, teeth和dental evidence兩對(duì)同義替換詞，很多同學(xué)會(huì)很堅(jiān)定的選擇III。很可惜，本題的正確答案是II。前文中我們提過，II 和 III選項(xiàng)較為類似，不同的是III中包含了Greenberg 這個(gè)人名也多出了linguistic這個(gè)信息。 III選項(xiàng)錯(cuò)誤的原因就是 Greenberg這個(gè)人物在文中只是個(gè)語言學(xué)家沒有研究過牙科證據(jù)，而這一信息恰恰出現(xiàn)在文章中唯一不需要閱讀的最后一段。所以，本題題目的設(shè)計(jì)是相當(dāng)精妙的?？忌坏x擇出能概括段落的選項(xiàng)，還不能忘記所選答案一定要是正確的。

所以，從以上的分析可以看出， List of Headings這類題型是對(duì)學(xué)生英語能力的考察?？忌茈y像部分細(xì)節(jié)題一樣根據(jù)一個(gè)經(jīng)驗(yàn)猜測(cè)答案。但是只要掌握了正確的做題原則還是可以事半功倍。