托福閱讀指代題四大類代詞關(guān)系梳理
托福閱讀指代題雖然考的是代詞，卻暗含著對指代關(guān)系、語篇邏輯的深層考察，并非單純詞匯層面的考察。根據(jù)代詞的不同類別，我們把托福閱讀指代題分成四大類型：人稱代詞類、指示代詞類、關(guān)系代詞類和不定代詞類。具體請看下文!
托福閱讀指代題四大類代詞關(guān)系梳理
托福閱讀考試中指代題是不可忽視的一大題型，雖然考的是代詞，卻暗含著對指代關(guān)系、語篇邏輯的深層考察，并非單純詞匯層面的考察。通常的提問形式體現(xiàn)為“The word they/their/it/its/some in the passage refers to______”，然后給出四個選項，這四個詞通常都是原文中出現(xiàn)過的生詞，并且往往都是在they/their/it/its/some這幾個詞的附近，需要考生經(jīng)過嚴(yán)密思考推測，選出一個既符合行文邏輯又符合上下文意思的選項。
那么我們?nèi)绾蚊鞔_判斷代詞所指代的對應(yīng)內(nèi)容呢?我們可以根據(jù)代詞的不同類別，把指代題分成四大類型：人稱代詞類、指示代詞類、關(guān)系代詞類和不定代詞類。然后就可以根據(jù)不同類別的代詞特征一一解答了。下面我們來具體看一下四大類代詞的特征及輔助解答托福閱讀指代題的策略。
第一類，人稱代詞
人稱代詞主要包括：I，you，he，she，it，we，they，me，him，them，yours，his，her，its，their等。此類題型應(yīng)在做題時根據(jù)代詞的單復(fù)數(shù)及其所能指代的名詞來判斷，通常是往前找最近的核心名詞。
例如：
“An auction is a popular way of buying and selling. It is a useful way of deciding the value of things?！?/p>
The word It in the passage refers to __________。
A. theory B. price
C. process D. auction
往前追溯單數(shù)形式的核心名詞，并且能用在第二句的主語位置的詞，就只能是第一句中出現(xiàn)的auction一詞了，所以正確答案選D。
第二類，指示代詞
指示代詞主要包括this, that, these, those等。在這種句子中，this和that通常指代某個觀點事物或現(xiàn)象，而these和those通常指復(fù)數(shù)形式下的某些觀點事物或意見，并且該類題也遵循往前找的原則。
例如：
“The dragon also has large claws that are used when it is younger. It uses these to climb trees to escape from the jaws of older dragons. But when they get older， these claws are used mainly as weapons?！?/p>
The word these in the passage refers to __________。
A. claws B. trees
C. jaws D. weapons
該題中的these一定是指之前已經(jīng)出現(xiàn)過的名詞，所以現(xiàn)在才能用代詞進(jìn)行指示，因此我們首先可通過往前追溯的原則進(jìn)行排出，B、C、D瞬間就都被排除了。再將A選項帶入原句驗證，看邏輯和意思是否與句意相符，最終驗證表明，答案正是A選項。
第三類，關(guān)系代詞
主要包括which, that, who, whom等。在這種句子中，通常采用就近原則。尤其是由“， which”格式引導(dǎo)的從句，一般都是非限制性定語從句，通常就是指該詞前面緊挨著的名詞。但需要注意的是，當(dāng)關(guān)系代詞前有插入語時，需要先去掉插入語，再使用就近原則。
例如：
“Scientists have been looking for energy sources to replace oil. They have studied wind，ethanol，and nuclear energy. They have also started to look at coal again. Coal，which is the cheapest energy source，is found in many parts of the world. However，it is dangerous to mine. It also pollutes the environment?！?/p>
The word which in the passage refers to __________。
A. nuclear energy B. ethanol
C. wind D. coal
一看詞句考察的是由which引導(dǎo)的非限制性定語從句，則毫不猶豫得把答案定位到which前的名詞“coal”上，所以一眼就能選出該題的正確答案D選項。
第四類，不定代詞
主要包括some，any，every，each，none，some...others...，one...,another等。這類代詞通常指的都是該詞前后與其關(guān)系最緊密的名詞主語，并且注意詞的單復(fù)數(shù)形式。
例如：
“Some studies show that one in eight plant species is threatened with extinction. It is estimated that 140000 species of plants are lost each year. Many of these lost plants could have been very useful in creating new drugs to combat disease?！?/p>
The word Many in the passage refers to __________。
A. studies B. plant species
C. lost plants D. new drugs
首先確定該題的“Many”所在句主語應(yīng)該是指“l(fā)ost plants”，并且“of”是表示所屬的關(guān)系，所以“Many”應(yīng)該是屬于“these lost plants”中的一部分，所以很顯然“Many”指的就應(yīng)該是“l(fā)ost plants”，因此答案選C。
需要注意的是這四大類代詞只能大致涵蓋托福閱讀指代題中所涉及的大致類型，要想全面把握托福閱讀指代題，我們還是需要把握好真題，結(jié)合解題技巧與策略進(jìn)行有針對性的練習(xí)與總結(jié)，循序漸進(jìn)提高托福閱讀水平與分?jǐn)?shù)。
托福閱讀指代題解題思路及步驟
一、問題形式
被考的文章中有一個詞或詞組被加亮，這個詞通常是一個代詞或名詞。指代題的形式如下：
The word (or phrase) X in the passage refers to
二、解題步驟
1. 根據(jù)解題技巧確定答案
2. 代入原文驗證，看語義、邏輯和語法上是否通順
三、基本原則
1. 就近指代
所謂就近指代，就是被指代對象通常在指代詞前不遠(yuǎn)處，如本句或上一句中。有時也出現(xiàn)在更前面的一句中。例如，
Large wind farms might also interfere with the flight patterns of migratory birds in certain areas, and they have killed large birds of prey (especially hawks, falcons, and eagles) that prefer to hunt along the same ridge lines that are ideal for wind turbines. The killing of birds of prey by wind turbines has pitted environmentalists who champion wildlife protection against environmentalists who promote renewable wind energy. Researchers are evaluating how serious this problem is and hope to find ways to eliminate or sharply reduce this problem.
The phrase this problem in the passage refers to interference with the flight patterns of migrating birds in certain areas building ridge lines that are ideal for wind turbines the killing of birds of prey by wind turbines meeting the demands of environmentalists who promote renewable wind energy
本題涉及的是一個詞組this problem。尋找這一詞組的指代對象時只需向上搜索就行。根據(jù)就近原則，前一句中的主語the killing of birds of prey by wind turbines可以初步確定為答案。將其代入原文，符合語義和邏輯，因此第三個選項為正確答案。第一個選項和第三個選項都和this problem相距較遠(yuǎn)，而且代入時語義和邏輯上不通，因此為干擾選項。
2. 數(shù)格一致
被指代對象通常與指代詞在數(shù)(如單數(shù)或復(fù)數(shù))和格(主格或賓格)兩方面相同。如單數(shù)代詞one指代單數(shù)名詞，復(fù)數(shù)代詞they指代復(fù)數(shù)名詞。
四、主要思路
1. 主從復(fù)合句中的指代
在主從復(fù)合句中，第二句的代詞主語經(jīng)常指代第一句的名詞主語。例如，
The fins are stiff, smooth, and narrow, qualities that also help cut drag. When not in use, the fins are tucked into special grooves or depressions so that they lie flush with the body and do not break up its smooth contours.
The word they in the passage refers to
?qualities
?fins
?grooves
?depressions
在這一例子中，從句so that they…中的代詞主語they指代主句的名詞主語the fins，因此第二個選項為正確答案。
新托福閱讀背景知識：植物適應(yīng)沙漠
Plant adaptation to the desert(背景材料)
Cactus adaptations.
The secret to the superior endurance of cacti lies in their adaptations. Over millions of years, through natural selection, only the strongest and best adapted species survived.
As you know, it is very dry in the desert. Plants that adapt to this are known as xerophytes (from zeros, dry and python, plant). There are plants that avoid the dry season by sprouting from seed just after the spring rain and growing very fast so that by the time the dry season comes, they have already produced a lot of seeds and died. These seeds lie on the soil for the dry season and sprout again in spring and the cycle repeats. Other xerophytes simply drop their leaves and stay dormant for the winter. But there is another special type of xerophytes which stores water in its fleshy tissues. Such plants are called succulents (from success, juicy). The cactus is a typical example of a succulent.
If you cut a cactus open, you see a juicy, slimy tissue. This is where the moisture is stored for the dry season. The part between the middle circle (and pith) and just under the very green part of the plant (or palisade parenchyma) just under the skin is allocated for the storage of water and food for the plant. This is a type of spongy parenchyma and can take up to 85% of the plant's volume. This is a major adaptation in the desert. Because the plant remains completely alive during the dry season and there is no need for it to dry up and lose everything, makes it possible for the plant to grow to large sizes. Another advantage is that the plant retains supplies (in the form of starch) for the winter so that it can flower right away in spring without accumulating more supplies (as most plants need to do in spring). The whole purpose of storing supplies for the winter is mostly to energize flowering in spring but it also lets the cactus start growing much sooner.
Flowering plants breathe and transpire (evaporate water from their surface) through closeable microscopic pores called stoats on the leaves or stems. To do this, their pores have to be open. In most plants these are open all day and on warm nights. But for cacti this is inconvenient as in daytime it is very hot and thus the plant would lose a lot of water through evaporation. So the cactus must close them in the daytime. But then it cannot breathe or photosynthesize (the process where sugars are made from carbon dioxide and water and releasing oxygen using the sun's energy). Succulents have an adaptation to that. Their stoats are closed during the day and are open at night, when it is not that hot and store carbon dioxide in its tissues as crass lean acid and then turn it back to carbon dioxide in the daytime. This process is called crass lean acid metabolism or CAM and it is a very smart way of respiring in the desert.
If we look at the outside of the plant, we notice that there is a tough leathery skin covering the plant, we can also notice the presence of ribs and spines and sometimes fur. These are all very smart adaptations. They serve mainly for surviving heat but are also used as defense.
The tough leathery skin is very impermeable to water, thus reducing evaporation from the surface of the plant. This skin often has a layer of plant wax on it which is often lightly colored (Pilosocereus azures is an example of a plant with such wax), white or blue. This reflects light and also reduces evaporation from the inside.
The ribs are special structures that are also used for enduring extreme heat. The ribs (and spines) trap wind so that the plant is enveloped in a layer of extremely still air, and this is a very important factor in reducing evaporation. On very windy days even the ribs don't help and cacti sometimes wilt because of high water loss.
The spines have different functions. They not only help shade the plant from the sun but are also known to help the cactus absorb water. They do it like this. On cool nights, dew settles on the spines of the plant. The spines are actually known to draw droplets of water towards the areole (the point out of which the spines grow) and here the droplets are absorbed. You can try this at home. Spray the plants with a very fine mist of water and watch what happens to the droplets that settle on the spines. They literally get attracted to the areole along the spine. The spine's structure allows them to do this. Even spines pointing downwards seem to suck the droplets up themselves.
Adaptation features are visible in this Pilosocereus glauchochorous. Notice the spines, ribs, fur and wax (the blue coloration). The top of a typically adapted plant.
Some plants have fur; sometimes all over the plant, sometimes only near the top. This fur shades the plant even further and is also known to attract water towards the areole. Some plants only have fur near the top. This is very beneficial because the top of the plant is very sensitive to sunlight, new tissues get formed there. Young areoles, with their spines not even wooded yet can get dried up completely in the sun. When an areole is born near the top of the plant, it starts developing spines. At this time the fur appears as well. This fur accompanies the areole as it moves down the plant, shading the growing point inside. By the time the areole is about 15cm away from the top, the fur wears out completely and the now inactive areole gets exposed to the sun.
As for the roots of cacti, they are also fully adapted to living in the desert. Some species (especially plants from very dry deserts) have very shallow root systems that spread very far from the plant. This way the plant can take advantage of tiny amounts of moisture from dew or light rain as the roots spread far away and are very shallow (less than 10cm deep while spreading up to 5 meters from the parent plant). On the other hand, some cacti send their roots deep down (like many Echinocacti) to reach the ground water.
Rainforest cacti often have aerial roots that can collect water all the time when it rains (and it rains very often in South American forests).
The shape of cacti itself is an adaptation. You may have noticed that cacti have a barrel like or candle like shape. This allows for maximum internal volume with a minimum surface area, which is also very smart adaption as a cactus can store a lot of water and have a small external surface area to reduce water loss.
托福閱讀指代題四大類代詞關(guān)系梳理相關(guān)文章：