黄金29篇真题经典难句收集Saavedro.doc

黄金29篇真题经典难句收集1. Only the last of these was suited at all to the continuous operating of machines, and although waterpower abounded in Lancashire and Scotland and ran grain mills as well as textile mills, it had one great disadvantage：Streams flowed where nature intended them to and water-driven factories had to be located on their banks whether or not the location was desirable for other reasons.2. Early in the century, a pump had come into use in which expanding steam raised a piston(活塞) in a cylinder(汽缸)，and atmospheric pressure brought it down again when the steam condensed inside the cylinder to form a vacuum3. The final step came when steam was introduced into the cylinder to drive the piston backward as well as forward thereby increasing the speed of the engine and cutting its fuel consumption.4. Coal gas rivaled smoky oil lamps and flickering candles, and early in the new century, welltodo Londoners grow accustomed to gaslights houses and even streets. 5. Iron manufacturers which had starved for fuel while depending on charcoal also benefited from ever-increasing supplies of coal; blast furnaces with steam-powered bellows turned out more iron and steel for the new machinery6. At the same time, operators of the first printing presses run by steam rather than by hand found it possible to produce a thousand pages in an hour rather than thirty7. In some industrial regions, heavily laden wagons，with flanged wheels，were being hauled by horses along metal rails; and the stationary steam engine was puffing in the factory and mine.8. Another generation passed before Inventors succeeded in combining these ingredients by putting the engine on wheels and the wheels on the rails, so as to provide a machine to take the place of the horse. 9. When he grew older William Smith taught himself surveying from books he bought with his small savings and at the age of eighteen he was apprenticed to a surveyor of the local parish. 10. The companies building the canals to transport coal needed surveyors to help them find the coal deposits worth mining as well as to determine the best courses for the canals. 11. He later worked on similar jobs across the length and breadth of England all the while studying the newly revealed strata and collecting all the fossils he could find12. But as more and more accumulations of strata were cataloged in more and more places, it became clear that the sequences of rocks sometimes differed from region to region and that no rock type was ever going to become a reliable time marker throughout the world. 13. Quartz is quartza silicon ion surrounded by four oxygen ions theres no difference at all between two-million-year-old Pleistocene quartz and Cambrian quartz created over 500 million years ago14. As he collected fossils from strata throughout England, Smith began to see that the fossils told a different story from the rocks particularly in the younger strata the rocks were often so similar that he had trouble distinguishing the strata, but he never had trouble telling the fossils apart. 15. While rock between two consistent strata might in one place be shale and in sandstone, the fossils in that shale or sandstone were always the same. 16. Some fossils endured through so many millions of years that they appear in many strata, but others occur only in a few strata, and a few species had their births and extinctions within one particular stratum. 17. By following the fossils, Smith was able to put all the strata of England's earth into relative temporal sequence. 18. Limestone may be found in the Cambrian or-300 million years later-in the Jurassic strata but a trilobitethe ubiquitous marine arthropod that had its birth in the Cambrianwill never be found in Jurassic strata, nor a dinosaur in the Cambrian.19. The sheer passage of time does not account for it; adults have excellent recognition of pictures of people who attended high school with them 35 years earlier. 20. Children two and a half to three years old remember experiences that occurred in their first year, and eleven month older than them can remember some events a year later. 21. Nor does the hypothesis that infantile amnesia reflects repression- or holding back- of sexually charged episodes explain the phenomenon.22. Maturation of the frontal lobes of the brain continues throughout early childhood, and this part of the brain may be critical for remembering particular episodes in ways that can be retrieved later. 23. Consistent with this view parents and children increasingly engage in discussions of past events when children are about three years old. 24. The better able the person is to reconstruct the perspective from which the material was encoded, the more likely that recall will be successful. 25. The world looks very different to a person whose head is only two or three feet above the ground than to one whose head is five or six feet above it, 0lder children and adults often try to retrieve the names of things they saw, but infants would not have encoded the information verbally26. Conversely，improved encoding of what they hear may help them better understand and remember stories and thus make the stories more useful for remembering future events.27. Missing until recently were fossils clearly intermediate, or transitional, between land mammals and cetaceans.28. Pakicetus was found embedded in rocks formed from river deposits that were 52 million years old. 29. 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.30. Several skeletons of another early whale, Basilosaurus, were found in sediments left by the Tethys Sea and now exposed in the Sahara desert. 31. The expansion of desert like conditions into areas where they did not previously exist is called desertification.32. In some cases the loose soil is blown completely away, leaving a stony surface. 33. Desertification is accomplished primarily through the loss of stabilizing natural vegetation and the subsequent accelerated erosion of the soil by wind and water. 34. The impact of raindrops on the loose soil tends to transfer fine clay particles into the tiniest soil spaces, sealing them and producing a surface that allows very little water penetration. 35. The gradual drying of the soil caused by its diminished ability to absorb water results in the further loss of vegetation, so that a cycle of progressive surface deterioration is established. 36. In some regions, the increase in desert areas is occurring largely as the result of a trend toward drier climatic conditions. 37. The process may be accelerated in subsequent decades if global warming resulting from air pollution seriously increases. 38. The semiarid lands bordering the deserts exist in a delicate ecological balance and are limited in their potential to adjust to increased environmental pressures. 39. During the dry periods that are common phenomena along the desert margins, though, the pressure on the land is often far in excess of its diminished capacity, and desertification results. 40. Since the raising of most crops necessitates the prior removal of the natural vegetation, crop failures leave extensive tracts of land devoid of a plant cover and susceptible to wind and water erosion. 41. The consequences of an excessive number of livestock grazing in an area are the reduction of the vegetation cover and the trampling and pulverization of the soil.42. The increased pressures of expanding populations have led to the removal of woody plants so that many cities and towns are surrounded by large areas completely lacking in trees and shrubs. 43. The increasing use of dried animal waste as a substitute fuel has also hurt the soil because this valuable soil conditioner and source of plant nutrients is no longer being returned to the land. 44. The water evaporates and the salts are left behind, creating a white crustal layer that prevents air and water from reaching the underlying soil. 45. 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.46. 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. 47. The cinema did not emerge as a form of mass consumption until its technology evolved from the initial "peepshow" format to the point where images were projected on a screen in a darkened theater. 48. For the price of 25 cents (or 5 cents per machine), customers moved from machine to machine to watch five different films (or, in the case of famous prizefights, successive rounds of a single fight).49. 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.50. 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.51. Exhibitors, however, wanted to maximize their profits, which they could do more readily by projecting a handful of films to hundreds of customers at a time (rather than one at a time) and by charging 25 to 50 cents admission.52. But the movies differed significantly from these other forms of entertainment, which depended on either live performance or (in the case of the slide-and-lantern shows) the active involvement of a master of ceremonies who assembled the final program.53. Although early exhibitors regularly accompanied movies with live acts, the substance of the movies themselves is mass-produced, prerecorded material that can easily be reproduced by theaters with little or no active participation by the exhibitor. 54. Even though early exhibitors shaped their film programs by mixing films and other entertainments together in whichever way they thought would be most attractive to audiences or by accompanying them with lectures, their creative control remained limited. 55. What audiences came to see was the technological marvel of the movies; the lifelike reproduction of the commonplace motion of trains, of waves striking the shore, and of people walking in the street; and the magic made possible by trick photography and the manipulation of the camera.56. With the advent of projection, the viewer's relationship with the image was no longer private, as it had been with earlier peepshow devices such as the Kinetoscope and the Mutoscope, which was a similar machine that reproduced motion by means of successive images on individual photographic cards instead of on strips of celluloid. 57. At the same time, the image that the spectator looked at expanded from the minuscule peepshow dimensions of 1 or 2 inches (in height) to the life-size proportions of 6 or 9 feet.58. Those individuals who possess characteristics that provide them with an advantage in the struggle for existence are more likely to survive and contribute their genes to the next generation.59. Because aggressive individuals are more likely to survive and reproduce, whatever genes are linked to aggressive behavior are more likely to be transmitted to subsequent generations.60. One is that people's capacity to outwit other species, not their aggressiveness, appears to be the dominant factor in human survival.61. Another is that there is too much variation among people to believe that they are dominated by, or at the mercy of, aggressive impulses.62. 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.63. 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.64. 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.65. 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.66. Goods produced by factories were not as finished or elegant as those done by hand, and pride in craftsmanship gave way to the pressure to increase rates of productivity.67. Factory life necessitated a more regimented schedule, where work began at the sound of a bell and workers kept machines going at a constant pace.68. Industrialization not only produced a fundamental change in the way work was organized; it transformed the very nature of work.69. The labor movement gathered some momentum in the decade before the Panic of 1837, but in the depression that followed, labor's strength collapsed.70. More than a decade of agitation did finally bring a workday shortened to 10 hours to most industries by the 1850s, and the courts also recognized workers' right to strike, but these gains had little immediate impact.71. Interestingly enough, several of these hydrodynamic adaptations resemble features designed to improve the aerodynamics of high-speed aircraft.72. They are also covered with a slick, transparent lid that reduces drag.73. 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.74. The keels, finlets, and corselet help direct the flow of water over the body surface in such as way as to reduce resistance (see the figure).75. One potential problem is that opening the mouth to breathe detracts from the streamlining of these fishes and tends to slow them down.76. Their high, narrow tails with swept-back tips are almost perfectly adapted to provide propulsion with the least possible effort.77. They can glide past eddies that would slow them down and then gain extra thrust by "pushing off" the eddies.78. They have evolved special "heaters" of modified muscle tissue that warm the eyes and brain, maintaining peak performance of these critical organs.79. 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 be