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1、2012年12月2日托福阅读真题解析阅读1版本i宇宙的两个理论，一个说物质会变化但总量不变，一个是会膨胀，最后说一个 遥远的恒星的发现说明后一个理论更正确；版本2：讲的是universe expanding的两种理论，一个是density在变小。另一种是 den sity不变。因为不断new creation补充变大的空间，然后发现了一种q.它表明前一种理 论更可信。解析：big-ba ng modelwidely held theory of the evoluti on of the uni verse. Its esse ntial feature is the emerge nee o
2、f the uni verse from a state of extremely high temperature and den sity-the so-called big bang that occurred at least 10,000,000,000 years ago. Although this type of uni verse was proposed by Alexa nder Friedma nn and Abbe Georges Lema?tre in the 1920s, the moder n versi on was developed by George G
3、amow and colleagues in the 1940s.The big-ba ng model is based on two assumpti ons. The first is that Albert Ein ste ins gen eral theory of relativity correctly describes the gravitati onal in teracti on of all matter. The second assumption, called the cosmological principle, states that an observers
4、 view of the uni verse depe nds n either on the directi on in which he looks nor on his locati on. This pri nciple applies only to the large-scale properties of the uni verse, but it does imply that the uni verse has no edge, so that the big-ba ng orig in occurred not at a particular point in space
5、but rather throughout space at the same time. These two assumptions make it possible to calculate the history of the cosmos after a certain epoch called the Planek time. Scientists have yet to determine what prevailed before Planck time.Accord ing to the big-ba ng model, the uni verse expa nded rapi
6、dly from a highly compressed primordial state, which resulted in a significant decrease in density and temperature. Soon afterward, the dom inance of matter over an timatter (as observed today) may have bee n established by processes that also predict prot on decay. Dur ing this stage many types of
7、eleme ntary particles may have bee n prese nt. After a few sec on ds, the uni verse cooled eno ugh to allow the formati on of certa in nu clei. The theory predicts that defi nite amo unts of hydroge n, helium, and lithium were produced. Their abundan ces agree with what is observed today. About 1,00
8、0,000 years later the uni verse was sufficie ntly cool for atoms to form. The radiati on that also filled the uni verse was the n free to travel through space. This rem nant of the early uni verse is the microwave backgro und radiati on (three degree backgro und radiati on) discovered in 1965 by Arn
9、o A. Pen zias and Robert W. Wilso n.In additi on to acco unting for the prese nee of ord in ary matter and radiati on, the model predicts that the prese nt uni verse should also be filled with n eutr ino s, f un dame ntal particles with no mass or electric charge. The possibility exists that other r
10、elics from the early uni verse may eve ntually be discovered.expa nding uni versedyn amic state of the extragalactic realm, the discovery of which has tra nsformed 20th-century cosmology. The development of general relativity and its application to cosmology by Albert Ein ste in, Wilhelm de Sitter,
11、and other theoreticia ns, along with the detecti on of extragalactic redshift (a shift to the Ion ger wavele ngths of light from galaxies beyo nd the Milky Way) by VestoSlipher, led to the realizatio n in the 1920s that all galaxies are reced ing. Edw in Hubble correlated these observati ons in math
12、ematical form to provide evide nee that the uni verse is expa nding. The discovery of the 2.7 K backgro und radiati on in 1965 by Arno A. Pen zias and Robert W. Wils on is regarded as convincing evide nee that the uni verse orig in ated approximately 15 billi on years ago in a very dense and hot sta
13、te referred to as the big bang (seebig-ba ng model).Observati ons so far have not succeeded in determ ining whether the uni verse is ope n (of in fi nite exte nt in space) or closed (of fin ite exte nt) and whether the uni verse in the future will continue to expa nd in defi nitely or will eve ntual
14、ly collapse back into an extremely den se, con gested state. See also cosmology.阅读2版本1：草原上的三种食草动物，斑马羊，还有一个B。他们吃草的不同的部分。把草的各 个部分坐对比，斑马的diet最没营养，因为蛋白质少，题目问你斑马怎么吃饱。羊吃的最有营 养题目问你为什么。然后讲过渡放牧，他们之间没有竞争，相处的较和谐。羊反而会prefer那 些已经被斑马吃过的草地而不是全新的草地版本2：讲了非洲的一片地区有很多种大型食草的哺乳动物，斑马，羚羊和一个什么white 的东西看上去像牛他们在吃草的时候会互补，因为他们吃
15、的是植物不同的地方。其中羚羊获取得 营养的最多，斑马的营养最少，但是斑马靠一个大的胃储存的多。解析：与0G测试题非常相似，请参考-Feed ing Habits of East Africa n HerbivoresBuffalo, zebras, wildebeests, topi, and Thoms ons gazelles live in huge groups that together make up some 90 percent of the total weight of mammals living on the Serengeti Pla in of East Afric
16、a. They are all herbivores (pla nt-eati ng ani mals), and they all appear to be liv ing on the same diet of grasses, herbs, and small bushes. This appeara nee, however, is illusory. When biologist Richard Bell and his colleagues analyzed the stomach contents of four of the five species (they did not study buffalo), they found that each species was living on a differe nt part of the vegetati on. The differe nt vegetati onal parts differ in their food qual
