1、托福(阅读)模拟试卷 14及答案与解析 一、 Sections Three: Reading Comprehension 0 “Four Stages of Planetary Development“ Planetary Development The planet Earth has passed through four-stages of planetary development. All terrestrial planets pass through these same stages to some degree, but some planets evolved furthe
2、r or were affected in different ways. The Four Stages The first stage of planetary evolution is differentiation, the separation of material according to density. Earth now has a dense core and a lower-density crust, and that structure must have originated very early in its history. Differentiation w
3、ould have occurred easily if Earth were molten when it was young. Two sources of energy could have heated Earth. First, heat of formation was released by in-falling material. A meteorite hitting Earth at high velocity converts most of its energy of motion into heat, and the impacts of a large number
4、 of meteorites would have released tremendous heat. If Earth formed rapidly, this heat would have accumulated much more rapidly than it could leak away, and Earth was probably molten when it formed. A second source of heat requires more time to develop. The decay of radioactive elements trapped in t
5、he Earth releases heat gradually; but, as soon as Earth formed, that heat began to accumulate and helped melt Earth. That would have helped the planet differentiate. While Earth was still in a molten state, meteorites could leave no trace, but in the second stage in planetary evolution, cratering, t
6、he young Earth was battered by meteorites that pulverized the newly forming crust. The largest meteorites blasted out crater basins hundreds of kilometers in diameter. As the solar nebula cleared, the amount of debris decreased, and after the late heavy bombardment, the level of cratering fell to it
7、s present low level. Although meteorites still occasionally strike Earth and dig craters, cratering is no longer the dominant influence on Earths geology. As you compare other worlds with Earth, you will discover traces of this intense period of cratering, on every old surface in the solar system. T
8、he third stage, flooding, no doubt began while cratering was still intense. The fracturing of the crust and the heating produced by radioactive decay allowed molten rock just below the crust to well up through fissures and flood the deeper basins. You will find such flooded basins with solidified la
9、va flows on other worlds, such as the moon, but all traces of this early lava flooding have been destroyed by later geological activity in Earths crust. On Earth, flooding continued as the atmosphere cooled and water fell as rain, filling the deepest basins to produce the first oceans. A Notice that
10、 on Earth flooding involves both lava and water, a circumstance that we will not find on most worlds. B The fourth stage, slow surface evolution, has continued for the last 3.5 billion years or more. C Earths surface is constantly changing as sections of crust slide over each other, push up mountain
11、s, and shift continents. D Almost all traces of the first billion years of Earths geology have been destroyed by the active crust and erosion. Earth as a Planet All terrestrial planets pass through these four stages, but some have emphasized one stage over another, and some planets have failed to pr
12、ogress fully through the four stages. Earth is a good standard for comparative planetology because every major process on any rocky world in our solar system is represented in some form on Earth. Nevertheless, Earth is peculiar in two ways. First, it has large amounts of liquid water on its surface.
13、 Fully 75 percent of its surface is covered by this liquid; no other planet in our solar system is known to have such extensive liquid water on its surface. Water not only fills the oceans but also evaporates into the atmosphere, forms clouds, and then falls as rain. Water falling on the continents
14、flows downhill to form rivers that flow back to the sea, and in so doing, the water produces intense erosion. You will not see such intense erosion on most worlds. Liquid water is, in fact, a rare material on most planets. Your home planet is special in a second way. Some of the matter on the surfac
15、e of this world is alive, and a small part of that living matter is aware. No one is sure how the presence of living matter has affected the evolution of Earth, but this process seems to be totally missing from other worlds in our solar system. Furthermore, the thinking part of life on Earth, humank
16、ind, is actively altering our planet. Glossary meteorite: a mass that falls to the surface of a planet from space planetology: the study of planets 1 Why does the author mention the “Earth“ in paragraph 1 ? ( A) To explain the stages in planetary development for the Earth in detail ( B) To contrast
17、the evolution of the Earth with that of other planets ( C) To demonstrate that the Earth passed through similar stages to those of most planets ( D) To give an example of exploration of the terrestrial planets 2 The word its in the passage refers to ( A) meteorite ( B) Earth ( C) velocity ( D) motio
18、n 3 Which of the sentences below best expresses the information in the highlighted statement in the passage? The other choices change the meaning or leave out important information. ( A) The Earth may have been liquid because the heat collected faster than it dissipated if the formation took place q
19、uickly. ( B) Because of the rapid formation of the Earth, the crust took a long time to cool before it became a solid. ( C) The liquid core of the Earth was created when the planet first formed because the heat was so high and there was little cooling. ( D) The cooling caused the Earth to form much
20、more quickly as it met with the intense heat of the new planet. 4 The word pulverized in the passage is closest in meaning to ( A) melted into liquid ( B) broken into small parts ( C) frozen very hard ( D) washed very clean 5 The word dominant in the passage is closest in meaning to ( A) most limite
21、d ( B) most likely ( C) most rapid ( D) most important 6 What can be inferred about radioactive matter? ( A) It is revealed by later activity. ( B) It generates intense heat. ( C) It is an important stage. ( D) it floods the planets crust. 7 According to paragraph 4, how were the oceans formed? ( A)
22、 Ice gouged out depressions in the Earth. ( B) Rain filled the craters made by meteorites. ( C) Earthquakes shifted the continents. ( D) Molten rock and lava flooded the basins. 8 What is the authors opinion of life on other planets? ( A) She does not know whether life is present on other planets. (
23、 B) She is certain that no life exists on any planet except Earth. ( C) She does not express an opinion about life on other planets. ( D) She thinks that there is probably life on other planets. 9 According to the passage, which stage occurs after cratering? ( A) Flooding ( B) Slow surface evolution
24、 ( C) Differentiation ( D) Erosion 10 All of the following are reasons why the Earth is a good model of planetary development for purposes of comparison with other planets EXCEPT ( A) The Earth has gone through all four stages of planetary evolution. ( B) Life on Earth has affected the evolution in
25、a number of important ways. ( C) All of the fundamental processes on terrestrial planets have occurred on Earth. ( D) There is evidence of extensive cratering both on Earth and on all other planets. 11 The word peculiar in the passage is closest in meaning to ( A) different ( B) better ( C) interest
26、ing ( D) new 12 Look at the four squares that show where the following sentence could be inserted in the passage. At the same time, moving air and water erode the surface and wear away geological features. Where could the sentence best be added? Click on a square to insert the sentence in the passag
27、e. 13 An introduction for a short summary of the passage appears below. Complete the summary by selecting the THREE answer choices that mention the most important points in the passage. Some sentences do not belong in the summary because they express ideas that are not included in the passage or are
28、 minor points from the passage. This question is worth 2 points. There are four stages of development for the terrestrial planets. - - - Answer Choices A All rocky planets go through different stages in their evolution because of variations in composition. B In spite of several unique features, the
29、Earth is a good example of how a planet proceeds through the stages. C Fewer meteorites fall to Earth now than in the earlier stages of the planets evolutionary history. D About three quarters of the surface of the Earth is submerged by the water in its oceans. E Differentiation and cratering are ea
30、rly stages that are influenced by in-falling meteorites. F Flooding includes both lava and water, while slow surface evolution causes shifting in the crust. 13 “Speech and Writing“ One of the basic assumptions of modern linguistics is that speech is primary and writing is secondary. The most immedia
31、te manifestation of language is speech and not writing. Writing is simply the representation of speech in another physical medium. Spoken language encodes thought into a physically transmittable form, while writing, in turn, encodes spoken language into a physically preservable form. Writing is a th
32、ree-stage process: thinking of an idea, expressing it in mental grammar, and then transferring it to written form. All units of writing, whether letters or characters, are based on units of speech, i.e., words, sounds, or syllables. When linguists study language, therefore, they take the spoken lang
33、uage as their best source of data and their object of description except in instances of languages like Latin for which there are no longer any speakers. You may think that with the advent of so many “instant messaging“ programs, writing can now be as immediate as speech. But it is important to reme
34、mber that even though the written form can be nearly immediate these days, there is still an extra step between conceptualizing the message you want to communicate and the reception of that idea, if you have to write it regardless of whether you do so longhand or type it into a computer. There are s
35、everal reasons for maintaining that speech is primary and writing is secondary. A Writing is a later historical development than spoken language. B Archeological evidence indicates that writing was first utilized in Sumer, that is, modern-day Iraq, about 6,000 years ago. C As far as physical and cul
36、tural anthropologists can tell, spoken language has probably been used by humans for hundreds of thousands of years. D Writing does not exist everywhere that spoken language does. This seems hard to imagine in our highly literate society, but the fact is that there are still many communities in the
37、world where a written form of language is not used. Even in those cultures using a writing system, there are individuals who fail to learn the written form of their language. In fact, the majority of the Earths inhabitants are illiterate, though quite capable of spoken communication. However, no soc
38、iety uses only a written language with no spoken form. Writing must be taught, whereas spoken language is acquired automatically. All children, except children with serious learning disabilities, naturally learn to speak the language of the community in which they are brought up. They acquire the ba
39、sics of their native language before they enter school, and even if they never attend school, they become fully competent speakers. Writing systems vary in complexity, but regardless of their level of sophistication, they must all be taught. Neurolinguistic evidence (studies of the brain in action d
40、uring language use) demonstrates that the processing and production of written language is overlaid on the spoken language centers in the brain. Spoken language involves several distinct areas of the brain; writing uses these areas and others as well. Despite all this evidence, it is a widely held m
41、isconception that writing is more perfect than speech. To many people, writing somehow seems more correct and more stable, whereas speech can be careless, corrupted, and susceptible to change. Some people even go so far as to identify “language“ with writing and to regard speech as a secondary form
42、of language used imperfectly to approximate the ideals of the written language. What gives rise to the misconception that writing is more perfect than speech? There are several reasons. Writing can be edited, and so the product of writing is usually more aptly worded and better organized, containing
43、 fewer errors, hesitations, and incomplete sentences than are found in speech. This “perfection of writing“ can be explained by the fact that writing is the result of deliberation, correction, and revision, while speech is the spontaneous and simultaneous formulation of ideas; writing is therefore l
44、ess subject to the constraint of time than speech is. Writing must be taught and is therefore ultimately associated with education and educated speech. Since the speech of the educated is more often than not set up as the “standard language,“ writing is associated indirectly with the varieties of la
45、nguage that people tend to view as “correct.“ However, the association of writing with the standard variety is not a necessary one, as evidenced by the attempts of writers to transcribe faithfully the speech of their characters. Mark Twains Huckleberry Finn and John Steinbecks Of Mice and Men contai
46、n examples of this. Writing is more physically stable than spoken language, which consists of nothing more than sound waves traveling through the air, and is therefore ephemeral and transient. Writing tends to last, because of its physical medium (characters on some surface), and can be preserved fo
47、r a very long time. Spelling does not seem to vary from individual to individual or from place to place as easily as pronunciation does. Thus, writing has the appearance of being more stable especially in the modern era. Of course, spelling does vary, as exemplified by the differences between the Am
48、erican ways of spelling gray and words with the suffixes -ize and -ization as compared with the British spelling of grey and -ise and -isation. Writing could also change if it were made to follow the changes of speech. The fact that people at various times try to carry out spelling reforms amply ill
49、ustrates this possibility. 14 According to paragraph 1, what can be inferred about linguistic research? ( A) Linguists do not usually study Latin. ( B) Research on writing is much easier. ( C) Studies always require several sources. ( D) Researchers prefer speech samples. 15 According to paragraph 4, what is true about literacy? ( A) Only a minority of the worlds population can read and write. ( B) Literate populations are more capable than other groups. ( C) The modern world has a very highly literate population. ( D) Many people fail to become literate because i
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