阅读理解

Directions: Read the following passages and answer the questions. Choose the most appropriate answer for each question and circle the letter on the answer sheet. Remember to write the letter corresponding to the question number. 


The Alaska pipeline starts at the frozen edge of the Arctic Ocean. It stretches southward across the largest and northernmost state in the United States, ending at a remote ice-free seaport village nearly 800 miles from where it begins. It is massive in size and extremely complicated to operate. 

The steel pipe crosses windswept plains and endless miles of delicate tundra(冻土带) that tops the frozen ground. It weaves through crooked canyons, climbs sheer mountains, plunges over rocky crags, makes its way through thick forests, and passes over or under hundreds of rivers and streams. The pipe is 4 feet in diameter, and up to 2 million barrels (or 84 million gallons) of crude oil can be pumped through it daily. 

Resting on H-shaped steel racks called “bents,” long sections of the pipeline follow a zigzag course high above the frozen earth. Other long sections drop out of sight beneath spongy or rocky ground and return to the surface later on. The pattern of the pipeline’s up-and-down route is determined by the often harsh demands of the arctic and subarctic climate, the tortuous lay of the land, and the varied compositions of soil, rock, or permafrost (permanently frozen ground). A little more than half of the pipeline is elevated above the ground. The remainder is buried anywhere from 3 to 12 feet, depending largely upon the type of terrain and the properties of the soil. 

One of the largest in the world, the pipeline cost approximately $8 billion and is by far the biggest and most expensive construction project ever undertaken by private industry. In fact, no single business could raise that much money, so 8 major oil companies formed a consortium in order to share the costs. Each company controlled oil rights to particular shares of land in the oil fields and paid into the pipeline-construction fund according to the size of its holdings. Today, despite enormous problems of climate, supply shortages, equipment breakdowns, labor disagreements, treacherous terrain, a certain amount of mismanagement, and even theft, the Alaska pipeline has been completed and is operating. 

单选题 The passage primarily discusses the pipeline’s _____.
【正确答案】 D
【答案解析】文章第二段详细介绍了阿拉斯加管道的具体情况，如规模、形状等，第四段第一句也提到了它是目前为止私有企业进行的最浩大、最昂贵的工程。因此可知全文是围绕管道的建设展开的，并没有提及它的运行费用、员工和消费者，因此选D项。
单选题 The word “it” in line 3 refers to _____.
【正确答案】 A
【答案解析】原文第一段第一句以the Alaska pipeline开始， 介绍了它的起点、范围， 最后介绍了尺寸及难以操作， 由此可知最后一句中的it应与第二句中的it同样指代pipeline。 因此本题选A项。
单选题 The phrase “Resting on” in line 1, paragraph 3 is closest in meaning to_____.
【正确答案】 B
【答案解析】根据第三段第一句可知， 在H型的铁架上， 管道长长的一部分在冻土地面上空呈“之”字形。 由此可以推测出H型的铁架对管道起到了支撑的作用， 因此本题选B项。
单选题 he author mentions all of the following as important in determining thepipeline’s route EXCEPT the _____.
【正确答案】 C
【答案解析】由关键词“决定管道路线的因素”可定位至第三段第三句， “The pattern of the pipeline’s up-and-down route is determined by…”， 管道的格局是由严寒的气候、 复杂的地形和构造各异的土壤、 岩石决定的。 因此本题选C项。
单选题 Which of the following determined what percentage of the constructioncosts each member of the consortium would pay?
【正确答案】 A
【答案解析】最后一段倒数第二句提到“Each company controlled oil rights to particular shares of land in the oil fields and paid into the pipeline-construction fund according to the size of its holdings.”， 各公司根据其持有的油田份额而支付相应的建设费， 因此本题选A项。