【备考必备】托福TPO8阅读长难句资料汇总.doc

【备考必备】托福TPO8阅读长难句资料汇总在这里小编为大家带来托福TPO8阅读长难句，希望对大家提高托福阅读水平有所帮助!托福TPO8阅读长难句TPO8: The Rise of Teotihuacan 1. Among the main factors are Teotihuacns geographic location on a natural trade routeto the south and east of the Valley of Mexico, the obsidian resources in the TeotihuacnValley itself, and the valleys potential for extensive irrigation.2. The exact role of other factors is much more difficult to pinpointfor instance,Teotihuacns religious significance as a shrine, the historical situation in and around theValley of Mexico toward the end of the first millennium B.C., the ingenuity andforesightedness of Teotihuacns elite, and, finally, the impact of natural disasters, suchas the volcanic eruptions of the late first millennium B.C.3. The hard volcanic stone was a resource that had been in great demand for many years,at least since the rise of the Olmecs (a people who flourished between 1200 and 400 B.C.),and it apparently had a secure market.TPO8: Extinction of the Dinosaurs1. Critics also point out that the shallow seaways had retreated from and advanced on thecontinents numerous times during the Mesozoic, so why did the dinosaurs survive theclimatic changes associated with the earlier fluctuations but not with this one?2. Scientists felt that they could get an idea of how long the extinctions took bydetermining how long it took to deposit this one centimeter of clay and they thought theycould determine the time it took to deposit the clay by determining the amount of theelement iridium (Ir) it contained.3. Their calculations show that the impact kicked up a dust cloud that cut off sunlight forseveral months, inhibiting photosynthesis in plants; decreased surface temperatures oncontinents to below freezing; caused extreme episodes of acid rain; and significantlyraised long-term global temperatures through the greenhouse effect.托福TPO8阅读长难句TPO8: Running water on Mars 1. The onrushing water arising from these flash floods likely also formed the oddteardrop-shaped “islands” (resembling the miniature versions seen in the wet sand of ourbeaches at low tide) that have been found on the plains close to the ends of the outflowchannels.2. Judging from the width and depth of the channels, the flow rates must have been trulyenormousperhaps as much as a hundred times greater than the 105 tons per secondcarried by the great Amazon river.3. A 2003 Mars Global Surveyor image shows what mission specialists think may be adeltaa fan-shaped network of channels and sediments where a river once flowed into alarger body of water, in this case a lake filling a crater in the southern highlands.4. But detractors maintain that the terraces could also have been created by geologicalactivity, perhaps related to the geologic forces that depressed the Northern Hemispherefar below the level of the south, in which case they have nothing whatever to do withMartian water.5. Furthermore, Mars Global Surveyor data released in 2003 seem to indicate that theMartian surface contains too few carbonate rock layerslayers containing compounds ofcarbon and oxygenthat should have been formed in abundance in an ancient ocean.6. Aside from some small-scale gullies (channels) found since 2000, which areinconclusive, astronomers have no direct evidence for l