托福阅读阅读真题长难句50句

托福阅读阅读真题长难句50句精选阅读真题长难句50句 1、 Later experiments in which researchers played recordings of songs to young birds showed just how precise this influence was, many of them would learn the exact pattern of the recording they had heard. 2、 The crude song of a bird reared in isolation gives some clues as to what this rough idea may be the length, the frequency range and the breaking up into notes are all aspects of chaffinch song shared between normal birds and those reared in isolation. 3、 Whatever the nature of the learning rules in a particular species, there is no doubt that they are effective, it is very unusual to hear a wild bird singing a song which is not typical of its own species despite the many different songs which often occur in a small patch of woodland. 4、 Chemical analysis of bones enables archaeologists to determine the proportion of meat to vegetable foods in the diet by measuring the proportion of calcium to strontium in ancient bone because strontium in place of calcium in bones comes primarily from ingested plants. 5、 Each dwelling had a different arrangement of the giant bones, which came from the skeletons of long-dead animals retrieved from the surrounding area by occupants of the site, not from animals they had recently hunted. 6、 In a precedent-setting decision, the Federal Energy Regulatory Commission ordered the dam removed after concluding that the environmental and economic benefits of a free-flowing river outweighed the electricity generated by the dam. 7、 Built nearly a century ago to provide power to lumber and paper mills in the town of Port Angeles, these dams blocked access to upstream spawning beds for six species of salmon on what once was one of the most productive salmon rivers in the world. 8、 The Hetch Hetchy Dam in Yosemite National Park might be taken down to reveal what John Muir, the founder of the prestigious environmental organization Sierra Club, called a valley “just as beautiful and worthy of preservation as the majestic Yosemite.” 9、 A chance collision between two comets, or the gravitational influence of one of the Jovian planetsJupiter, Saturn, Uranus, and Neptunemay occasionally alter the orbit of a comet in these regions enough to send it to the inner solar system and into our view. 10、 These comets appear to be distributed in all directions from the Sun, forming a spherical shell around the solar system, called the Oort cloud, after the Dutch astronomer Jan Oort. 11、 After the arrival of hunter-gatherers in the southwestern region of North America, several alternative types of agriculture emerged, all involving different solutions to the Southwests fundamental problem: how to obtain enough water to grow crops in an environment in which rainfall is so low and unpredictable that little or no farming is practiced there today. 12、 That fate actually befell the Mimbres, who started by farming the floodplain and then began to farm adjacent land above the floodplain as their population came to exceed the floodplains capacity to support it. 13、 However, when drought conditions returned, that gamble left them with a population double what the floodplain could support, and Mimbres society collapsed suddenly under the stress. 14、 One more strategy was to plant crops at many sites even though rainfall was locally unpredictable and then to harvest crops at whichever sites did get enough rain to produce a good harvest and to redistribute some of the harvest to the people still living at all the sites that did not happen to receive enough rain that year. 15、 Sanitation problems caused by larger, more sedentary populations would have helped transmit diseases in human waste, as would the use of animal dung for fertilizer. 16、 The increase in many of these came not only from the fact that fewer people were dying from infectious disease and were living longer but also from the results of modern lifestyles in developed countries and among the upper classes of developing countries a more sedentary life leading to less physical activity, more stress; environmental pollution, and high-fat diets. 17、 This evolution may have been encouraged by what some authorities consider our overuse of antibiotics, giving microorganisms a greater chance to evolve resistance by exposing them to a constant barrage of selective challenges. 18、 Therefore, on many reefs it is the fast-growing, branching corals that ultimately dominate at the upper, shallower portion of the reef, whereas more massive forms dominate in deeper areas. 19、 The fact that almost all small invertebrates on reefs are so well hidden or highly camouflaged is another indicator of how prevalent predation is on reefs and its importance in determining reef structure.