Passage 26 問題解決型（專業(yè)性科學(xué)文章）
提出四個標準——提出問題In choosing a method for determining climatic conditions that existed in the past, paleoclimatologists invoke four principal criteria*2C. First, the material—rocks, lakes, vegetation, etc.—on which the method relies must be widespread*7 enough to provide plenty of information, since（小原因，可以暫時不看） analysis of material that is rarely encountered will not permit correlation with other regions or with other periods*7 of geological history. Second, in the process of formation, the material must have received an environmental signal that reflects a change in climate and that can be deciphered破譯，解碼 by modern physical or chemical means. Third, at least some of the material must have retained the signal *6unaffected by subsequent changes in the environment*6D. Fourth, it must be possible to determine the time at which the inferred climatic conditions held. This last criterion is more easily（比較句，很可能出題） met in dating marine sediments*1, because（小原因，暫時不用看） dating of only a small number of layers in a marine sequence allows the age of other layers to be estimated fairly reliably by extrapolation and interpolation. By contrast（強對比，一定要看）, because（小原因，暫時不用看，看后半句） sedimentation is much less continuous*1E in continental regions*1, estimating the age of a continental bed from the known ages of beds above and below is more risky.
解決方案一：古代湖泊水位法One very old（大-） method*2C used in the investigation of past climatic conditions involves the measurement of water levels in ancient lakes. 原因一In temperate regions溫帶地區(qū), there are enough lakes for correlations between them to give us a reliable（小+，由于前面有大，所以后面一定有轉(zhuǎn)折） picture. In arid and semiarid regions, on the other hand（轉(zhuǎn)折）, the small number of lakes and the great distances between them reduce the possibilities for correlation. 原因二Moreover（大列舉的非第一點）, since lake levels are controlled by rates of evaporation as well as（強調(diào)前者） by precipitation降水, the interpretation of such levels is ambiguous*5B（-）. For instance（與結(jié)論緊密相連，篇幅小，可以暫時不看）, the fact that lake levels in the semiarid southwestern United States*5 appear to have been higher during the last ice age than they are now was at one time attributed to increased precipitation. On the basis of snow-line elevations*3, however（其實還是緊跟上一個例子，可以暫時不看）, it has been concluded*3 that the climate then was not necessarily wetter than it is now, but rather that both summers and winters were cooler, resulting in reduced evaporation*3E.
解決方案二：花粉法Another problematic（大-） method is to reconstruct former climates on the basis of pollen profiles. The type of vegetation in a specific region is determined by identifying and counting（by doing通常都是很重要的內(nèi)容） the various pollen grains found there. Although（轉(zhuǎn)折的前半句可以不讀） the relationship between vegetation and climate is not as direct as the relationship between climate and lake levels, the method often works well（小+） in the temperate zones. In arid and semiarid regions in which there is not much vegetation（-）, however, small changes in one or a few plant types can change the picture dramatically, making accurate correlations between neighboring areas difficult*8A（-） to obtain.
缺正確解決方案：看過程不看結(jié)果
1. Which of the following statements about the difference between marine and continental sedimentation*1 is supported by information in the passage?信息題（有定位，第一段最后一點）AD無，BC反
(A) Data provided by dating marine sedimentation is more consistent with 沒提到researchers’ findings in other disciplines than is data provided by dating continental sedimentation.
(B) It is easier to estimate the age of a layer in a sequence of continental sedimentation 說反了than it is to estimate the age of a layer in a sequence of marine sedimentation.
(C) Marine sedimentation is much less widespread說反了 than continental sedimentation.
(D) Researchers are more often forced to rely on extrapolation沒這么說 when dating a layer of marine sedimentation than when dating a layer of continental sedimentation.（E）
(E) Marine sedimentation is much more continuous*1E than is continental sedimentation.
2. Which of the following statements best describes the organization of the passage as a whole?主題題（寫法性）
(A) The author describes a method for determining past climatic conditions and then offers specific examples of situations in which it has been used.
(B) The author discusses the method of dating marine and continental sequences and then explains how dating is more difficult with lake levels than with pollen profiles.
(C) The author describes the common requirements*2C of methods for determining past climatic conditions and then discusses examples of such methods*2C.問題解決型
(D) The author describes various ways of choosing a material for determining past climatic conditions and then discusses how two such methods have yielded contradictory data.（C）
(E) The author describes how methods for determining past climatic conditions were first developed and then describes two of the earliest known methods.
3. It can be inferred from the passage that paleoclimatologists have concluded*3 which of the following on the basis of their study of snow-line elevations*3 in the southwestern United States?
(A) There is usually more precipitation during an ice age because of increased amounts of evaporation.
(B) There was less precipitation during the last ice age than there is today.
(C) Lake levels in the semiarid southwestern United States were lower during the last ice age than they are today.
(D) During the last ice age, cooler weather led to lower lake levels than paleoclimatologists had previously assumed.（E）
(E) The high lake levels during the last ice age may have been a result of less evaporation rather than more precipitation*3E.
4. Which of the following would be the most likely topic for a paragraph that logically continues the passage?主題題（寫法性）
(A) The kinds of plants normally found in arid regions
(B) The effect of variation in lake levels on pollen distribution
(C) The material best suited to preserving signals of climatic changes
(D) Other criteria invoked by paleoclimatologists when choosing a method to determine past climatic conditions（E）
(E) A third method for investigating past climatic conditions本文缺正確的解決方案
5. The author discusses lake levels in the southwestern United States*5 in order to舉例作用題（竅門法：illustrate, give/provide an example of；標準法：For instance, For example, such as, like——結(jié)論在前）
(A) illustrate the mechanics of the relationship between lake level, evaporation, and precipitation
(B) provide an example of the uncertainty*5B involved in interpreting lake levels
(C) prove that there are not enough ancient lakes with which to make accurate correlations
(D) explain the effects of increased rates of evaporation on levels of precipitation（B）
(E) suggest that snow-line elevations are invariably more accurate than lake levels in determining rates of precipitation at various points in the past
6. It can be inferred from the passage that an environmental signal*6（第二、第三個標準都講到了，不過這里考的是第三個標準） found in geological material would not be useful to paleoclimatologists if it改善題的變體（回文中找優(yōu)點——本文是要求、標準，然后取非）
(A) had to be interpreted by modern chemical means
(B) reflected a change in climate rather than a long-term climatic condition
(C) was incorporated into a material as the material was forming
(D) also reflected subsequent environmental changes*6D（D）
(E) was contained in a continental rather than a marine sequence
7. According to the passage, the material used to determine past climatic conditions must be widespread*7 for which of the following reasons?直接事實題（不要用非出題段落內(nèi)容來解題）
I. Paleoclimatologists need to make comparisons between periods*7 of geological history.
II. Paleoclimatologists need to compare materials that have supported a wide variety of vegetation.
III. Paleoclimatologists need to make comparisons with data collected in other regions*7.
(A) I only
(B) II only
(C) I and II only
(D) I and III only（D）
(E) II and III only
8. Which of the following can be inferred from the passage about the study of past climates in arid and semiarid regions（第二段和第三段，定位太廣，只能挨個答案看）?信息題BDE無，C反
(A) It is sometimes more difficult*8A to determine past climatic conditions in arid and semiarid regions than in temperate regions.
(B) Although in the past more research沒講過 has been done on temperate regions, paleoclimatologists have recently turned their attention to arid and semiarid regions.
(C) Although more information說反了 about past climates can be gathered in arid and semiarid than in temperate regions, dating this information is more difficult.
(D) It is difficult to study the climatic history of arid and semiarid regions because their climates have tended to vary more原因錯了 than those of temperate regions.（A）
(E) The study of past climates in arid and semiarid regions has been neglected不對 because temperate regions support a greater variety of plant and animal life.
提出四個標準——提出問題In choosing a method for determining climatic conditions that existed in the past, paleoclimatologists invoke four principal criteria*2C. First, the material—rocks, lakes, vegetation, etc.—on which the method relies must be widespread*7 enough to provide plenty of information, since（小原因，可以暫時不看） analysis of material that is rarely encountered will not permit correlation with other regions or with other periods*7 of geological history. Second, in the process of formation, the material must have received an environmental signal that reflects a change in climate and that can be deciphered破譯，解碼 by modern physical or chemical means. Third, at least some of the material must have retained the signal *6unaffected by subsequent changes in the environment*6D. Fourth, it must be possible to determine the time at which the inferred climatic conditions held. This last criterion is more easily（比較句，很可能出題） met in dating marine sediments*1, because（小原因，暫時不用看） dating of only a small number of layers in a marine sequence allows the age of other layers to be estimated fairly reliably by extrapolation and interpolation. By contrast（強對比，一定要看）, because（小原因，暫時不用看，看后半句） sedimentation is much less continuous*1E in continental regions*1, estimating the age of a continental bed from the known ages of beds above and below is more risky.
解決方案一：古代湖泊水位法One very old（大-） method*2C used in the investigation of past climatic conditions involves the measurement of water levels in ancient lakes. 原因一In temperate regions溫帶地區(qū), there are enough lakes for correlations between them to give us a reliable（小+，由于前面有大，所以后面一定有轉(zhuǎn)折） picture. In arid and semiarid regions, on the other hand（轉(zhuǎn)折）, the small number of lakes and the great distances between them reduce the possibilities for correlation. 原因二Moreover（大列舉的非第一點）, since lake levels are controlled by rates of evaporation as well as（強調(diào)前者） by precipitation降水, the interpretation of such levels is ambiguous*5B（-）. For instance（與結(jié)論緊密相連，篇幅小，可以暫時不看）, the fact that lake levels in the semiarid southwestern United States*5 appear to have been higher during the last ice age than they are now was at one time attributed to increased precipitation. On the basis of snow-line elevations*3, however（其實還是緊跟上一個例子，可以暫時不看）, it has been concluded*3 that the climate then was not necessarily wetter than it is now, but rather that both summers and winters were cooler, resulting in reduced evaporation*3E.
解決方案二：花粉法Another problematic（大-） method is to reconstruct former climates on the basis of pollen profiles. The type of vegetation in a specific region is determined by identifying and counting（by doing通常都是很重要的內(nèi)容） the various pollen grains found there. Although（轉(zhuǎn)折的前半句可以不讀） the relationship between vegetation and climate is not as direct as the relationship between climate and lake levels, the method often works well（小+） in the temperate zones. In arid and semiarid regions in which there is not much vegetation（-）, however, small changes in one or a few plant types can change the picture dramatically, making accurate correlations between neighboring areas difficult*8A（-） to obtain.
缺正確解決方案：看過程不看結(jié)果
1. Which of the following statements about the difference between marine and continental sedimentation*1 is supported by information in the passage?信息題（有定位，第一段最后一點）AD無，BC反
(A) Data provided by dating marine sedimentation is more consistent with 沒提到researchers’ findings in other disciplines than is data provided by dating continental sedimentation.
(B) It is easier to estimate the age of a layer in a sequence of continental sedimentation 說反了than it is to estimate the age of a layer in a sequence of marine sedimentation.
(C) Marine sedimentation is much less widespread說反了 than continental sedimentation.
(D) Researchers are more often forced to rely on extrapolation沒這么說 when dating a layer of marine sedimentation than when dating a layer of continental sedimentation.（E）
(E) Marine sedimentation is much more continuous*1E than is continental sedimentation.
2. Which of the following statements best describes the organization of the passage as a whole?主題題（寫法性）
(A) The author describes a method for determining past climatic conditions and then offers specific examples of situations in which it has been used.
(B) The author discusses the method of dating marine and continental sequences and then explains how dating is more difficult with lake levels than with pollen profiles.
(C) The author describes the common requirements*2C of methods for determining past climatic conditions and then discusses examples of such methods*2C.問題解決型
(D) The author describes various ways of choosing a material for determining past climatic conditions and then discusses how two such methods have yielded contradictory data.（C）
(E) The author describes how methods for determining past climatic conditions were first developed and then describes two of the earliest known methods.
3. It can be inferred from the passage that paleoclimatologists have concluded*3 which of the following on the basis of their study of snow-line elevations*3 in the southwestern United States?
(A) There is usually more precipitation during an ice age because of increased amounts of evaporation.
(B) There was less precipitation during the last ice age than there is today.
(C) Lake levels in the semiarid southwestern United States were lower during the last ice age than they are today.
(D) During the last ice age, cooler weather led to lower lake levels than paleoclimatologists had previously assumed.（E）
(E) The high lake levels during the last ice age may have been a result of less evaporation rather than more precipitation*3E.
4. Which of the following would be the most likely topic for a paragraph that logically continues the passage?主題題（寫法性）
(A) The kinds of plants normally found in arid regions
(B) The effect of variation in lake levels on pollen distribution
(C) The material best suited to preserving signals of climatic changes
(D) Other criteria invoked by paleoclimatologists when choosing a method to determine past climatic conditions（E）
(E) A third method for investigating past climatic conditions本文缺正確的解決方案
5. The author discusses lake levels in the southwestern United States*5 in order to舉例作用題（竅門法：illustrate, give/provide an example of；標準法：For instance, For example, such as, like——結(jié)論在前）
(A) illustrate the mechanics of the relationship between lake level, evaporation, and precipitation
(B) provide an example of the uncertainty*5B involved in interpreting lake levels
(C) prove that there are not enough ancient lakes with which to make accurate correlations
(D) explain the effects of increased rates of evaporation on levels of precipitation（B）
(E) suggest that snow-line elevations are invariably more accurate than lake levels in determining rates of precipitation at various points in the past
6. It can be inferred from the passage that an environmental signal*6（第二、第三個標準都講到了，不過這里考的是第三個標準） found in geological material would not be useful to paleoclimatologists if it改善題的變體（回文中找優(yōu)點——本文是要求、標準，然后取非）
(A) had to be interpreted by modern chemical means
(B) reflected a change in climate rather than a long-term climatic condition
(C) was incorporated into a material as the material was forming
(D) also reflected subsequent environmental changes*6D（D）
(E) was contained in a continental rather than a marine sequence
7. According to the passage, the material used to determine past climatic conditions must be widespread*7 for which of the following reasons?直接事實題（不要用非出題段落內(nèi)容來解題）
I. Paleoclimatologists need to make comparisons between periods*7 of geological history.
II. Paleoclimatologists need to compare materials that have supported a wide variety of vegetation.
III. Paleoclimatologists need to make comparisons with data collected in other regions*7.
(A) I only
(B) II only
(C) I and II only
(D) I and III only（D）
(E) II and III only
8. Which of the following can be inferred from the passage about the study of past climates in arid and semiarid regions（第二段和第三段，定位太廣，只能挨個答案看）?信息題BDE無，C反
(A) It is sometimes more difficult*8A to determine past climatic conditions in arid and semiarid regions than in temperate regions.
(B) Although in the past more research沒講過 has been done on temperate regions, paleoclimatologists have recently turned their attention to arid and semiarid regions.
(C) Although more information說反了 about past climates can be gathered in arid and semiarid than in temperate regions, dating this information is more difficult.
(D) It is difficult to study the climatic history of arid and semiarid regions because their climates have tended to vary more原因錯了 than those of temperate regions.（A）
(E) The study of past climates in arid and semiarid regions has been neglected不對 because temperate regions support a greater variety of plant and animal life.