本类题目考察对于句子主线的理解能力
Paragraph 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 of 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, AmbuIocetus 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. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage?
Incorrect choices change the meaning in important ways or leave out essential information.
○Even though Ambulocetus swam by moving its body up and down, it did not have a backbone.
○The backbone of Ambulocetus, which allowed it to swim, provides evidence of its missing fluke.
○Although Ambulocetus had no fluke, its backbone structure shows that it swam like modern whales.
○By moving the rear parts of their bodies up and down, modern whales swim in a different way from the way Ambulocetus swam.
Paragraph 10: The extreme seriousness of desertification results from the vast areas of land and the tremendous numbers of people affected, as well as from the great difficulty of reversing or even slowing the process. Once the soil has been removed by erosion, only the passage of centuries or millennia will enable new soil to form. In areas where considerable soil still remains, though, a rigorously enforced program of land protection and cover-crop planting may make it possible to reverse the present deterioration of the surface.
2. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage?
Incorrect choices change the meaning in important ways or leave out essential information.
○Desertification is a significant problem because it is so hard to reverse and affects large areas of land and great numbers of people.
○Slowing down the process of desertification is difficult because of population growth that has spread over large areas of land.
○The spread of deserts is considered a very serious problem that can be solved only if large numbers of people in various countries are involved in the effort.
○Desertification is extremely hard to reverse unless the population is reduced in the vast areas affected.
Paragraph 2: These Kinetoscope arcades were modeled on phonograph parlors, which had proven successful for Edison several years earlier. In the phonograph parlors, customers listened to recordings through individual ear tubes, moving from one machine to the next to hear different recorded speeches or pieces of music. The Kinetoscope parlors functioned in a similar way. Edison was more interested in the sale of Kinetoscopes (for roughly $1,000 apiece) to these parlors than in the films that would be run in them (which cost approximately $10 to $15 each). He refused to develop projection technology, reasoning that if he made and sold projectors, then exhibitors would purchase only one machine-a projector-from him instead of several.
3. Which of the sentences below best expresses the essential information in the highlighted sentence from the passage?
Incorrect answer choices change the meaning in important ways or leave out essential information.
○Edison was more interested in developing a variety of machines than in developing a technology based on only one.
○Edison refused to work on projection technology because he did not think exhibitors would replace their projectors with newer machines.
○Edison did not want to develop projection technology because it limited the number of machines he could sell.
○Edison would not develop projection technology unless exhibitors agreed to purchase more than one projector from him.
Paragraph 7: The Cognitive Approach. Cognitive psychologists assert that our behavior is influenced by our values, by the ways in which we interpret our situations and by choice. For example, people who believe that aggression is necessary and justified-as during wartime-are likely to act aggressively, whereas people who believe that a particular war or act of aggression is unjust, or who think that aggression is never justified, are less likely to behave aggressively.
Paragraph 8: One cognitive theory suggests that aggravating and painful events trigger unpleasant feelings. These feelings, in turn, can lead to aggressive action, but not automatically. Cognitive factors intervene. People decide whether they will act aggressively or not on the basis of factors such as their experiences with aggression and their interpretation of other people‘s motives. Supporting evidence comes from research showing that aggressive people often distort other people’s motives. For example, they assume that other people mean them harm when they do not.
4. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage?
Incorrect answer choices change the meaning in important ways or leave out essential information.
○People who believe that they are fighting a just war act aggressively while those who believe that they are fighting an unjust war do not.
○People who believe that aggression is necessary and justified are more likely to act aggressively than those who believe differently.
○People who normally do not believe that aggression is necessary and justified may act aggressively during wartime.
○People who believe that aggression is necessary and justified do not necessarily act aggressively during wartime.
Paragraph 2: The creation of a labor force that was accustomed to working in factories did not occur easily. Before the rise of the factory, artisans had worked within the home. Apprentices were considered part of the family, and masters were responsible not only for teaching their apprentices a trade but also for providing them some education and for supervising their moral behavior. Journeymen knew that if they perfected their skill, they could become respected master artisans with their own shops. Also, skilled artisans did not work by the clock, at a steady pace, but rather in bursts of intense labor alternating with more leisurely time.
5. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage?
Incorrect answer choices change the meaning in important ways or leave out essential information.
○Masters demanded moral behavior from apprentices but often treated them irresponsibly.
○The responsibilities of the master to the apprentice went beyond the teaching of a trade.
○Masters preferred to maintain the trade within the family by supervising and educating the younger family members.
○Masters who trained members of their own family as apprentices demanded excellence from them.
Paragraph 7: One potential problem is that opening the mouth to breathe detracts from the streamlining of these fishes and tends to slow them down. Some species of tuna have specialized grooves in their tongue. It is thought that these grooves help to channel water through the mouth and out the gill slits, thereby reducing water resistance.
6. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage?
Incorrect answer choices change the meaning in important ways or leave out essential information,
○These fishes often have a problem opening their mouths while swimming.
○The streamlining of these fishes prevents them from slowing down.
○The streamlining of these fishes tends to slow down their breathing.
○Opening the mouth to breathe can reduce the speed of these fishes.
Paragraph 6: In some ways the social makeup of the two parties was similar. To be competitive in winning votes, Whigs and Democrats both had to have significant support among farmers, the largest group in society, and workers. Neither party could win an election by appealing exclusively to the rich or the poor. The Whigs, however, enjoyed disproportionate strength among the business and commercial classes. Whigs appealed to planters who needed credit to finance their cotton and rice trade in the world market, to farmers who were eager to sell their surpluses, and to workers who wished to improve themselves. Democrats attracted farmers isolated from the market or uncomfortable with it, workers alienated from the emerging industrial system, and rising entrepreneurs who wanted to break monopolies and open the economy to newcomers like themselves. The Whigs were strongest in the towns, cities, and those rural areas that were fully integrated into the market economy, whereas Democrats dominated areas of semisubsistence farming that were more isolated and languishing economically.
7. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage?
Incorrect choices change the meaning in important ways or leave out essential information.
○Whigs were able to attract support only in the wealthiest parts of the economy because Democrats dominated in other areas.
○Whig and Democratic areas of influence were naturally split between urban and rural areas, respectively.
○The semisubsistence farming areas dominated by Democrats became increasingly isolated by the Whigs‘ control of the market economy.
○The Democrats’ power was greatest in poorer areas while the Whigs were strongest in those areas where the market was already fully operating.
Paragraph 2: Most investigators concur that certain facial expressions suggest the same emotions in all people. Moreover, people in diverse cultures recognize the emotions manifested by the facial expressions. In classic research Paul Ekman took photographs of people exhibiting the emotions of anger, disgust, fear, happiness, and sadness. He then asked people around the world to indicate what emotions were being depicted in them. Those queried ranged from European college students to members of the Fore, a tribe that dwells in the New Guinea highlands. All groups, including the Fore, who had almost no contact with Western culture, agreed on the portrayed emotions. The Fore also displayed familiar facial expressions when asked how they would respond if they were the characters in stories that called for basic emotional responses. Ekman and his colleagues more recently obtained similar results in a study of ten cultures in which participants were permitted to report that multiple emotions were shown by facial expressions. The participants generally agreed on which two emotions were being shown and which emotion was more intense.
8. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage?
Incorrect choices change the meaning in important ways or leave out essential information.
○The Fore‘s facial expressions indicated their unwillingness to pretend to be story characters.
○The Fore were asked to display familiar facial expressions when they told their stories.
○The Fore exhibited the same relationship of facial expressions and basic emotions that is seen in Western culture when they acted out stories.
○The Fore were familiar with the facial expressions and basic emotions of characters in stories.
Paragraph 2: Hills and mountains are often regarded as the epitome of permanence, successfully resisting the destructive forces of nature, but in fact they tend to be relatively short-lived in geological terms. As a general rule, the higher a mountain is, the more recently it was formed; for example, the high mountains of the Himalayas are only about 50 million years old. Lower mountains tend to be older, and are often the eroded relics of much higher mountain chains. About 400 million years ago, when the present-day continents of North America and Europe were joined, the Caledonian mountain chain was the same size as the modern Himalayas. Today, however, the relics of the Caledonian orogeny (mountain-building period) exist as the comparatively low mountains of Greenland, the northern Appalachians in the United States, the Scottish Highlands, and the Norwegian coastal plateau.
9. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage?
Incorrect choices change the meaning in important ways or leave out essential information.
○When they are relatively young, hills and mountains successfully resist the destructive forces of nature.
○Although they seem permanent, hills and mountains exist for a relatively short period of geological time.
○Hills and mountains successfully resist the destructive forces of nature, but only for a short time.
○Hills and mountains resist the destructive forces of nature better than other types of landforms.
Paragraph 9: The relative amount of these two kinds of water varies greatly from one kind of rock or sediment to another, even though their porosities may be the same. What happens depends on pore size. If the pores are large, the water in them will exist as drops too heavy for surface tension to hold, and it will drain away; but if the pores are small enough, the water in them will exist as thin films, too light to overcome the force of surface tension holding them in place; then the water will be firmly held.
10. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
○Surface tension is not strong enough to retain drops of water in rocks with large pores but it strong enough to hold on to thin films of water in rocks with small pores.
○Water in rocks is held in place by large pores and drains away from small size pores through surface tension.
○Small pores and large pores both interact with surface tension to determine whether a rock will hold water as heavy drops or as a thin film.
○If the force of surface tension is too weak to hold water in place as heavy drops, the water will continue to be held firmly in place as a thin film when large pores exist.
Paragraph 6: But neither the human imitative instinct nor a penchant for fantasy by itself leads to an autonomous theater. Therefore, additional explanations are needed. One necessary condition seems to be a somewhat detached view of human problems. For example, one sign of this condition is the appearance of the comic vision, since comedy requires sufficient detachment to view some deviations from social norms as ridiculous rather than as serious threats to the welfare of the entire group. Another condition that contributes to the development of autonomous theater is the emergence of the aesthetic sense. For example, some early societies ceased to consider certain rites essential to their well-being and abandoned them, nevertheless, they retained as parts of their oral tradition the myths that had grown up around the rites and admired them for their artistic qualities rather than for their religious usefulness.
11．Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
○A society’s rites were more likely to be retained in the oral tradition if its myths were admired for artistic qualities.
○The artistic quality of a myth was sometimes an essential reason for a society to abandon it from the oral tradition.
○Some early societies stopped using myths in their religious practices when rites ceased to be seen as useful for social well-being.
○Myths sometimes survived in a society’s tradition because of their artistic qualities even after they were no longer deemed religiously beneficial.
Paragraph 4：There is still no universally agreed-on explanation for why there should be such a dramatic cessation of tree growth at the upper timberline. Various environmental factors may play a role. Too much snow, for example, can smother trees, and avalanches and snow creep can damage or destroy them. Late-lying snow reduces the effective growing season to the point where seedlings cannot establish themselves. Wind velocity also increases with altitude and may cause serious stress for trees, as is made evident by the deformed shapes at high altitudes. Some scientists have proposed that the presence of increasing levels of ultraviolet light with elevation may play a role, while browsing and grazing animals like the ibex may be another contributing factor. Probably the most important environmental factor is temperature, for if the growing season is too short and temperatures are too low, tree shoots and buds cannot mature sufficiently to survive the winter months.
12. Which of the sentences below best express the essential information in the highlighted sentence in the passage? In correct choices change the meaning in important ways or leave out essential information.
○Because of their deformed shapes at high altitudes, trees are not likely to be seriously harmed by the strong winds typical of those altitudes.
○As altitude increases, the velocity of winds increase, leading to a serious decrease in the number of trees found at high altitudes.
○The deformed shapes of trees at high altitudes show that wind velocity, which increase with altitude, can cause serious hardship for trees.
○Increased wind velocity at high altitudes deforms the shapes of trees, and this may cause serious stress for trees.
Paragraph 3：In order for the structure to achieve the size and strength necessary to meet its purpose, architecture employs methods of support that, because they are based on physical laws, have changed little since people first discovered them-even while building materials have changed dramatically. The world’s architectural structures have also been devised in relation to the objective limitations of materials. Structures can be analyzed in terms of how they deal with downward forces created by gravity. They are designed to withstand the forces of compression (pushing together), tension (pulling apart), bending, or a combination of these in different parts of the structure.
13. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
○Unchanging physical laws have limited the size and strength of buildings that can be made with materials discovered long ago.
○Building materials have changed in order to increase architectural size and strength, but physical laws of structure have not changed.
○When people first started to build, the structural methods used to provide strength and size were inadequate because they were not based on physical laws.
○Unlike building materials, the methods of support used in architecture have not changed over time because they are based on physical laws.
Paragraph 2：The Ogallala aquifer is a sandstone formation that underlies some 583,000 square kilometers of land extending from northwestern Texas to southern South Dakota. Water from rains and melting snows has been accumulating in the Ogallala for the past 30,000 years. Estimates indicate that the aquifer contains enough water to fill Lake Huron, but unfortunately, under the semiarid climatic conditions that presently exist in the region, rates of addition to the aquifer are minimal, amounting to about half a centimeter a year.
14. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
○Despite the current impressive size of the Ogallala aquifer, the region’s climate keeps the rates of water addition very small.
○Although the aquifer has been adding water at the rate of only half a centimeter a year, it will eventually accumulate enough water of fill Lake Huron.
○Because of the region’s present climatic conditions, water is being added each year to the aquifer.
○Even when the region experiences unfortunate climatic conditions, the rates of addition of water continue to increase.
Paragraph 6: Ecologists are especially interested to know what factors contribute to the resilience of communities because climax communities all over the world are being severely damaged or destroyed by human activities. The destruction caused by the volcanic explosion of Mount St. Helens, in the northwestern United States, for example, pales in comparison to the destruction caused by humans. We need to know what aspects of a community are most important to the community’s resistance to destruction, as well as its recovery.
15．Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incurred choices change the meaning in important ways or leave out essential information.
○Ecologists now think that the stability of an environment is a result of diversity rather than patchiness.
○Patchy environments that vary from place to place do not often have high species diversity.
○Uniform environments cannot be climax communities because they do not support as many types of organisms as patchy environments.
○A patchy environment is thought to increase stability because it is able to support a wide variety of organisms.
Paragraph 4：Dandelions are good examples of opportunists. Their seed heads raised just high enough above the ground to catch the wind, the plants are no bigger than they need be, their stems are hollow, and all the rigidity comes from their water content. Thus, a minimum investment has been made in the body that becomes a platform for seed dispersal. These very short-lived plants reproduce prolifically; that is to say they provide a constant rain of seed in the neighborhood of parent plants. A new plant will spring up wherever a seed falls on a suitable soil surface, but because they do not build big bodies, they cannot compete with other plants for space, water, or sunlight. These plants are termed opportunists because they rely on their seeds’ falling into settings where competing plants have been removed by natural processes, such as along an eroding riverbank, on landslips, or where a tree falls and creates a gap in the forest canopy.
16. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
○Because their seeds grow in places where competing plants are no longer present, dandelions are classified as opportunists.
○Dandelions are called opportunists because they contribute to the natural processes of erosion and the creation of gaps in the forest canopy.
○The term opportunists apply to plants whose seeds fall in places where they can compete with the seeds of other plants.
○The term opportunists apply to plants whose falling seeds are removed by natural processes.
Paragraph 5: 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. Some analysts also contend that the number of birds killed by wind turbines is dwarfed by birds killed by other human-related sources and by the potential loss of entire bird species from possible global warming. Recorded deaths of birds of prey and other birds in wind farms in the United States currently amount to no more than 300 per year. By contrast, in the United States an estimated 97 million birds are killed each year when they collide with buildings made of plate glass, 57 million are killed on highways each year; at least 3.8 million die annually from pollution and poisoning; and millions of birds are electrocuted each year by transmission and distribution lines carrying power produced by nuclear and coal power plants.
17. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
○Hawks, falcons, and eagles prefer to hunt along ridge lines, where wind turbines can kill large numbers of migratory birds.
○Wind turbines occasionally cause migratory birds to change their flight patterns and therefore may interfere with the areas where birds of prey prefer to hunt.
○Some of the best locations for large wind farms are places that may cause problems for migrating birds and birds of prey.
○Large wind farms in certain areas kill hawks, falcons, and eagles and thus might create a more ideal path for the flight of migratory birds.
Paragraph 5：The causes of this population rebound are consequences of other human actions. First, the major predators of deer---wolves, cougar, and lynx--have been greatly reduced in numbers. Second, conservation has been insured by limiting times for and types of hunting. But the most profound reason for the restoration of high population numbers has been the gate of the forests. Great tracts of lowland country deforested by logging, fire, or both have become ideal feeding grounds of deer. In addition to finding an increase of suitable browse, like huckleberry and vine maple, Arthur Linares, longtime game biologist in the Pacific Northwest, found quality of browse in the open areas to be substantially more nutritive. The protein content of shade- grown vegetation, for example, was much lower than that for plants grown in clearings.
18．Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
○Arthur Einarsen’s longtime family with the Pacific Northwest helped him discover areas where deer had an increase in suitable browse.
○Arthur Einarsen found that deforested feeding grounds provided deer with more and better food.
○Biologist like Einarsen believe it is important to find additional open areas with suitable browse for deer to inhabit.
○According to Einarsen, huckleberry and vine maple are examples of vegetation that may someday improve the nutrition of deer in the open areas of the Pacific Northwest.
Paragraph 3：The subjects of the paintings are mostly animals. The paintings rest on bare walls, with no backdrops or environmental trappings. Perhaps, like many contemporary peoples, Upper Paleolithic men and women believed that the drawing of a human image could cause death of injury, and if that were indeed their belief, it might explain why human figures are rarely depicted in cave art. Another explanation for the focus on animals might be that these people sought to improve their luck at hunting. This theory is suggested by evidence of chips in the painted figures, perhaps made by spears thrown at the drawings. But if improving their hunting luck was the chief motivation for the paintings, it is difficult to explain why only a few show signs of having been speared. Perhaps the paintings were inspired by the need to increase the supply of animals. Cave art seems to have reached a peak toward the end of the Upper Paleolithic period, when the herds of game were decreasing.
19. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways of leave out essential information.
○Upper Paleolithic people, like many contemporary peoples, believed that if they drew a human image in their cave art, it would cause death or injury.
○Many contemporary people believe that the drawing of a human image can cause death or injury, so they, like Upper Paleolithic people, rarely depicted human figures in their cave art.
○If Upper Paleolithic people, like many contemporary peoples, believed that the drawing of a human image could cause death or injury, this belief might explain why human figures are rarely depicted in cave art.
○Although many contemporary peoples believe that the drawing of a human image can cause death or injury, researchers cannot explain why Upper Paleolithic people rarely depicted human figures in their cave art.
Paragraph 1—2：Petroleum, consisting of crude oil and natural gas, seems to originate from organic matter in marine sediment. Microscopic organisms settle to the seafloor and accumulate in marine mud. The organic matter may partially decompose, using up the dissolved oxygen in the sediment. As soon as the oxygen is gone, decay stops and the remaining organic matter is preserved.
Continued sedimentation—the process of deposits‘ settling on the sea bottom—buries the organic matter and subjects it to higher temperatures and pressures, which convert the organic matter to oil and gas. As muddy sediments are pressed together, the gas and small droplets of oil may be squeezed out of the mud and may move into sandy layers nearby. Over long periods of time (millions of years), accumulations of gas and oil can collect in the sandy layers. Both oil and gas are less dense than water, so they generally tend to rise upward through water-saturated rock and sediment.
20．Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
○Higher temperatures and pressures promote sedimentation, which is responsible for petroleum formation.
○Deposits of sediments on top of organic matter increase the temperature of and pressure on the matter.
○Increase pressure and heat from the weight of the sediment turn the organic remains into petroleum.
○The remains of microscopic organisms transform into petroleum once they are buried under mud.
Paragraph 1: Although we now tend to refer to the various crafts according to the materials used to construct them-clay, glass, wood, fiber, and metal-it was once common to think of crafts in terms of function, which led to their being known as the “applied arts.” Approaching crafts from the point of view of function, we can divide them into simple categories: containers, shelters and supports. There is no way around the fact that containers, shelters, and supports must be functional. The applied arts are thus bound by the laws of physics, which pertain to both the materials used in their making and the substances and things to be contained, supported, and sheltered. These laws are universal in their application, regardless of cultural beliefs, geography, or climate. If a pot has no bottom or has large openings in its sides, it could hardly be considered a container in any traditional sense. Since the laws of physics, not some arbitrary decision, have determined the general form of applied-art objects, they follow basic patterns, so much so that functional forms can vary only within certain limits. Buildings without roofs, for example, are unusual because they depart from the norm. However, not all functional objects are exactly alike; that is why we recognize a Shang Dynasty vase as being different from an Inca vase. What varies is not the basic form but the incidental details that do not obstruct the object’s primary function.
21. Which of the following best expresses the essential information in the highlighted sentence? Incorrect answer choices change the meaning in important ways or leave out essential information.
○Functional applied-art objects cannot vary much from the basic patterns determined by the laws of physics.
○The function of applied-art objects is determined by basic patterns in the laws of physics.
○Since functional applied-art objects vary only within certain limits, arbitrary decisions cannot have determined their general form.
○The general form of applied-art objects is limited by some arbitrary decision that is not determined by the laws of physics.
Paragraph 7: Earth is a target in a cosmic shooting gallery, subject to random violent events that were unsuspected a few decades ago. In 1991 the United States Congress asked NASA to investigate the hazard posed today by large impacts on Earth. The group conducting the study concluded from a detailed analysis that impacts from meteorites can indeed be hazardous. Although there is always some risk that a large impact could occur, careful study shows that this risk is quite small.
22. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
○Until recently, nobody realized that Earth is exposed to unpredictable violent impacts from space.
○In the last few decades, the risk of a random violent impact from space has increased.
○Since most violent events on Earth occur randomly, nobody can predict when or where they will happen.
○A few decades ago, Earth became the target of random violent events originating in outer space.
参考答案：
1. ○Although Ambulocetus had no fluke, its backbone structure shows that it swam like modern whales.
2. ○Desertification is a significant problem because it is so hard to reverse and affects large areas of land and great numbers of people.
3. ○Edison did not want to develop projection technology because it limited the number of machines he could sell.
4.○People who believe that aggression is necessary and justified are more likely to act aggressively than those who believe differently.
5.○The responsibilities of the master to the apprentice went beyond the teaching of a trade.
6.○Opening the mouth to breathe can reduce the speed of these fishes.
7.○The Democrats‘ power was greatest in poorer areas while the Whigs were strongest in those areas where the market was already fully operating.
8.○The Fore exhibited the same relationship of facial expressions and basic emotions that is seen in Western culture when they acted out stories.
9.○Although they seem permanent, hills and mountains exist for a relatively short period of geological time.
10. ○Surface tension is not strong enough to retain drops of water in rocks with large pores but it strong enough to hold on to thin films of water in rocks with small pores.
11. ○Myths sometimes survived in a society’s tradition because of their artistic qualities even after they were no longer deemed religiously beneficial.
12. ○The deformed shapes of trees at high altitudes show that wind velocity, which increase with altitude, can cause serious hardship for trees.
13. ○Unlike building materials, the methods of support used in architecture have not changed over time because they are based on physical laws.
14. ○Despite the current impressive size of the Ogallala aquifer, the region’s climate keeps the rates of water addition very small.
15. ○A patchy environment is thought to increase stability because it is able to support a wide variety of organisms.
16. ○Because their seeds grow in places where competing plants are no longer present, dandelions are classified as opportunists.
17. ○Some of the best locations for large wind farms are places that may cause problems for migrating birds and birds of prey.
18.○Arthur Einarsen found that deforested feeding grounds provided deer with more and better food.
19. ○If Upper Paleolithic people, like many contemporary peoples, believed that the drawing of a human image could cause death or injury, this belief might explain why human figures are rarely depicted in cave art.
20. ○Increase pressure and heat from the weight of the sediment turn the organic remains into petroleum.
21. ○Functional applied-art objects cannot vary much from the basic patterns determined by the laws of physics.
22. ○Until recently, nobody realized that Earth is exposed to unpredictable violent impacts from space.