1、大学英语六级模拟试卷 313及答案与解析 一、 Part I Writing (30 minutes) 1 Directions: For this part, you are allowed 30 minutes to write a composition on the topic An Invitation Letter. You should write at least 150 words following the outline given below in Chinese: 1. 请你以大学校长的名义给校友们写一封 100周年校庆的邀请信，指出邀请的时间 2. 简单介绍学校 3
2、. 告诉对方联系方式，表示期待 二、 Part II Reading Comprehension (Skimming and Scanning) (15 minutes) Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions attached to the passage. For questions 1-4, mark： Y (for YES) if the statement agrees with the information
3、given in the passage; N (for NO) if the statement contradicts the information given in the passage; NG (for NOT GIVEN) if the information is not given in the passage. 1 Trees To many, the word trees evokes images of such ancient, powerful, and majestic structures as the redwood and the giant sequoia
4、 (红杉 ), among the most massive and longest living organisms in the world. Although the majority of the Earths biomass is represented by trees, the fundamental importance of these seemingly ubiquitous plants for the very existence and diversity of life on Earth is perhaps not fully appreciated. Our v
5、ery biosphere is dependent on the metabolism, death, and recycling of plants, especially trees. Their vast trunks and root systems store carbon dioxide and water and respire oxygen into the atmosphere. The organic matter of the soil develops primarily from plant residues (that is, from decayed leave
6、s, twigs, branches, roots, and fallen trees), which release important nutrients, such as nitrogen, carbon, and oxygen. The tree is not an immutable biological category but rather a human concept based on visual criteria. Perhaps a general definition would describe a tree as a perennial(多年生的 ) woody
7、plant that develops along a single main trunk to a height of at least 4.5 metres at maturity. This may be contrasted with a shrub, which might be loosely defined as a woody plant with multiple stems; in most cases, a shrub is less than 3 metres tall. However, a species fitting the description of eit
8、her in one area of the world might not necessarily do so in other regions, since a variety of stresses shape the habit of the mature plant. Thus, a given woody species may be a tree in one set of habitats within its range and a shrub elsewhere. For example, the spruce and fir may thrive in the tree
9、form at the base of a mountain but assume a shrub form near the mountain-top, the variation due principally to stresses exerted by such environmental conditions as altitude, temperature, and oxygen tension. In the early stages of the development of terrestrial life, land plants were rootless and lea
10、fless, since they had their origins in aqueous environments, they did not require the specialized conducting and supporting tissues afforded by roots and stems, nor did they require localized regions of carbohydrate synthesis, since each cell was involved in metabolism, water and nutrient absorption
11、, and respiration. Habitats farther from the water as well as aerial habitats represented available uninhabited environments. One key to exploiting these habitats is large size. This, however, requires physiological and morphological (形态的 ) complexity. If all the tissues of massive tree trucks were
12、alive, for example, the physiological cost of maintaining these structures in the living state would be enormous, and probably unattainable. The elegant solution came in the form of tremendous structural adaptations, new tissues and organs permitted localization of the functions of the plant body. T
13、he evolution of vascular tissues and localized regions of cell division permitted the strengthening and conducting tissue, called wood, to be dead, hollow, thick-walled tubes at functional maturity. Roots provided anchorage and absorption of sufficient amounts of water and nutrients to support the h
14、uge biomass of the tree. Stems were not only strong enough to support the tree and project it into ever higher habitats but conductive enough to transport the water and nutrients to the leaves at the very top of the tree. The shape of a tree is an ecological construct as well, since its form is depe
15、ndent on the habitat and the stresses of the environment. Open-grown trees, such as those in gardens and parks, generally have foliage extending along the length of the trunk for a considerable distance. Forest trees, on the other hand, compete for growing space and generally have an expanse of foli
16、age-free bole below a more limited tree crown. The aggregate of the tree crowns constitutes the canopy of the forest, and this may be displayed in a single layer or stratified (分层 ) into several layers, depending on the number and kinds of trees that make up the forest. Forests are of immense import
17、ance in soil stabilization and erosion control, especially in mountainous and hilly regions; they also protect and conserve water supplies and prevent floods. Small groups of trees and even single trees have a similar role locally in preventing washouts and in holding stream banks. As mentioned abov
18、e, trees contribute significantly to nutrient recycling, carbon dioxide absorption, and oxygen generation. Carbonized and fossilized wood (coal) supplies fuel for energy needs; other fossilized products of trees include amber, which is formed from the gum of pines, and kauri gum (贝壳杉树胶 ). From earli
19、est times wood has been employed for such purpose as homes, rafts, canoes, fuel, and weapons. Primitive people were dependent on trees for many materials in addition to wood. Fruits and nuts of many kinds were important foods for both humans and animals. Leaves of palms and other trees were used for
20、 thatching roofs. Tapa cloth (构树皮布 ) and woven fabrics made from bark, leaves, and other tree parts were used for clothing. Utensils were fashioned from calabashes, coconuts, and other fruits. Medicines, including quinine, were obtained from trees, as were dyes, tanning materials, and spices. Modern
21、 civilizations are no less dependent on trees. Although substitutes now are commonly used for some tree products, the demand for trees remains strong, as in the manufacture of newsprint and other papers as well as cardboard and similar packagings. The plywood industry converts immense numbers of tre
22、es into building materials. Many tree products other than wood and its derivatives are important. Edible fruits produced by trees include apples, cherries, peaches, pears, and others in temperate climates; figs, persimmons, and citrus fruits (柑橘果 ) in warm-temperate and subtropical regions; breadfru
23、it, coconuts, jackfruit, and mangoes in tropical regions; and the important fruit of desert regions the date. The coconut, the oil plam, and the olive are important sources of oils and fats used as food and for other purposes. From trees come such spices as cinnamon (桂皮 ) and nutmeg; substances used
24、 in beverages, such as chocolate, coffee, and kola nuts; and chicle, the basis of chewing gum. It is true, however, that the history of civilization also includes incidences of waste, sometimes bordering on elimination of a species from a particular region. Great forests of cedars of Lebanon, for ex
25、ample, were virtually eliminated in lumbering operations during early historic times for such purposes as the construction of King Solomons great temple and palace. Forests that covered much of the Mediterranean region and Middle East were extravagantly exploited by the Assyrians, Babylonians, Greek
26、s, and Romans. Today the once vast Amazonian rain forest is in imminent danger of being deforested primarily for farmland. 2 In the beginning of the development of life on Earth, land plants originated in watery environment. （ A） Y （ B） N （ C） NG 3 Environmental conditions determine the variation of
27、 the growth of the tree. （ A） Y （ B） N （ C） NG 4 As vascular plants, trees are organized into three major organs: the roots, the stems, and the leaves. （ A） Y （ B） N （ C） NG 5 Formed from the gum of pines, amber is carbonized wood product. （ A） Y （ B） N （ C） NG 6 The fundamental importance of trees
28、for the life on Earth should _. 7 According to a general definition, a mature tree would be at least _. 8 The water and nutrients to support the biomass of the tree are provided by _ and conducted by _. 9 In mountainous regions forests stabilize _ and control _. 10 To thatch roofs, primitive peoples
29、 were dependent on _. 11 Modern civilizations are as dependent on trees as _. Section A Directions: In this section, you will hear 8 short conversations and 2 long conversations. At the end of each conversation, one or more questions will be asked about what was said. Both the conversation and the q
30、uestions will be spoken only once. After each question there will be a pause. During the pause, you must read the four choices marked A, B, C and D, and decide which is the best answer. （ A） He told Bob not to study late at night. （ B） He had often advised Bob to study. （ C） Bob is too tired to stud
31、y any more. （ D） Bob didnt hear the alarm. （ A） In Professor Browns office. （ B） In a university bookstore. （ C） In a publishers office. （ D） In a shipping company office. （ A） The man may have to reschedule his trip. （ B） The man should take his vacation somewhere else. （ C） She hasnt called the tr
32、avel agent yet. （ D） She doesnt know when her semester ends. （ A） Wash his red T-shirt again. （ B） Buy new white socks. （ C） Throw away his pink socks. （ D） Use bleach on his socks. （ A） He doesnt like coffee anymore. （ B） Hes already prepared the coffee. （ C） Hes had to eliminate coffee from his di
33、et. （ D） He has to take his medicine first. （ A） They have to wait for a long while to get the ticket. （ B） They will probably not be able to get the ticket. （ C） The tickets have already been sold out. （ D） They have to wait fifty minutes before they get the ticket. （ A） She doesnt want to waste he
34、r film. （ B） She doesnt know how to use the camera. （ C） She doesnt have any more film. （ D） She already took a picture of the mountains. （ A） The plants may need more light. （ B） The plants should get less water. （ C） The area in front of the window is too cold for plants. （ D） Plants rarely do wel
35、l in the dormitory. （ A） Working over time as a librarian. （ B） Writing papers for his classes. （ C） Meeting with his professors. （ D） Doing extra work in the chemistry lab. （ A） Do his research on closely related topics. （ B） Spend more time in the library. （ C） Write just one paper for all his cla
36、sses. （ D） Drop one of his courses. （ A） She doesnt need any help. （ B） She knows hes very busy. （ C） Hes already helped her enough. （ D） He doesnt know enough chemistry. （ A） She was impressed by it. （ B） It was a waste of money. （ C） She was amazed it had opened so soon. （ D） She didnt like it as
37、much as the other wings. （ A） He went for a tour of the city. （ B） He read about it. （ C） He wrote an article about it. （ D） He worked there as a guide. （ A） They came from the original wing. （ B） Theyre made of the same material. （ C） Theyre similar in shape. （ D） They were designed by the same per
38、son. （ A） It was made of aluminum. （ B） It wasnt large enough. （ C） It wouldnt move the wind. （ D） It was too heavy to put up. Section B Directions: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be s
39、poken only once. After you hear a question, you must choose the best answer from the four choices marked A, B, C and D. （ A） English is the easiest language to learn. （ B） English is as easy to learn as your mother tongue. （ C） English can be learnt in six weeks. （ D） It is easier to learn English o
40、n radio or TV. （ A） To speak English. （ B） To read technical books in English. （ C） To listen to English programs on radio. （ D） To read English literature. （ A） English learning at school usually takes a long time. （ B） More and more people want to learn English nowadays. （ C） It is not necessary f
41、or many people to go to English speaking countries to learn English. （ D） It is more difficult to learn English quickly than to learn it slowly. （ A） Because many people dont know how to behave in social situations. （ B） Because most people are shy by nature. （ C） Nobody will laugh at you for being
42、shy. （ D） Shyness is difficult to overcome. （ A） By prediction. （ B） By recording. （ C） Through observation. （ D） Through interviewing. （ A） To observe peoples attitude towards strangers. （ B） To see how people get along with their friends. （ C） To change peoples behaviour in social life. （ D） To fi
43、nd out how shy people are. （ A） The colonists preferred corn bread. （ B） Corn was more abundant. （ C） The colonists did not know how to make wheat bread. （ D） Corn bread did not spoil as rapidly as wheat bread did. （ A） It was easy to ship from England. （ B） Horses occasionally ate it if there was n
44、o grain available. （ C） People took it with them when they traveled. （ D） It was easy to prepare over an open fire in the forests. （ A） It tends to vary geographically. （ B） It corresponds to an individuals social class. （ C） It changes over a period of time. （ D） It depends on whether or not the in
45、dividual is a gourmet. （ A） Because it was more nutritious than other type of bread. （ B） Because it did not require yeast. （ C） Because it stayed fresh for a long time. （ D） Because it took less time to brake. Section C Directions: In this section, you will hear a passage three times. When the pass
46、age is read for the first time, you should listen carefully for its general idea. When the passage is read for the second time, you are required to fill in the blanks numbered from 36 to 43 with the exact words you have just heard. For blanks numbered from 44 to 46 you are required to fill in the mi
47、ssing information. For these blanks, you can either use the exact words you have just heard or write down the 36 It is often claimed that nuclear energy is something we cannot do without. We live in a consumer society where there is an enormous demand for commercial products of all kinds.【 B1】 _ ,an
48、 increase in industrial production is considered to be one solution to the problem of【 B2】 _ unemployment. Such an increase【 B3】_ an abundant and cheap energy supply. Many people believe that nuclear energy provides an【 B4】 _ and economical source of power and that it is【 B5】 essential for an indust
49、rially developing society. There are a number of other advantages in the use of nuclear energy. Firstly, nuclear power, except for accidents, is clean. A further advantage is that a nuclear power station can be run and【 B6】 _ by relatively few technical and administrative staff. The nuclear reactor【 B7】 _ an enormous step in our scientific evolution and, whatever the anti nuclear group says, it is wrong to expect a return to more【 B8】 _ sources
