新东方名师推荐:四六级优秀范文背诵(42)

最后冲刺

★ 2010年四六级备考手册：听力篇（更新中…）

★ 2010年四六级备考手册:阅读篇(更新中…)

★ 2010年四六级备考手册：写作篇（更新中…）

考前必备

★ 四级写作高分工具：新概念3常见词汇句法

★ 名师指导6月六级最后冲刺备考方法

★ 四六级名师传授绝技：5个词拿下快速阅读

★ 2010年6月六级听力考试场景词汇精要

★ 六级听力长对话短期突破：从真题入手

2010年6月四六级考试真题答案点评汇总

42.Coal-fired power plants

The invention of the incandescent light bulb by Thomas A. Edison in 1879 created a demand for a cheap, readily available fuel with which to generate large amounts of electric power. Coal seemed to fit the bill, and it fueled the earliest power stations. (which were set up at the end of the nineteenth century by Edison himself). As more power plants were constructed throughout the country, the reliance on coal increased throughout the country, the reliance on coal increased. Since the First World War, coal-fired power plants had a combined in the United States each year. In 1986 such plants had a combined generating capacity of 289,000 megawatts and consumed 83 percent of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty in the future growth of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty in the future growth of nuclear power and in the supply of oil and natural gas, coal-fired power plants could well provide up to 70 percent of the electric power in the United States by the end of the century.

Yet, in spite of the fact that coal has long been a source of electricity and may remain on for many years(coal represents about 80 percent of United States fossil-fuel reserves), it has actually never been the most desirable fossil fuel for power plants. Coal contains less energy per unit of weight than weight than natural gas or oil; it is difficult to transport, and it is associated with a host of environmental issues, among them acid rain. Since the late 1960’s problems of emission control and waste disposal have sharply reduced the appeal of coal-fired power plants. The cost of ameliorating these environment problems along with the rising cost of building a facility as large and complex as a coal-fired power plant, have also made such plants less attractive from a purely economic perspective.

Changes in the technological base of coal-fired power plants could restore their attractiveness, however. Whereas some of these changes are intended mainly to increase the productivity of existing plants, completely new technologies for burning coal cleanly are also being developed.

四级历年真题（2001-2009）

2001年1月	2001年6月	2002年1月	2002年6月	2003年1月
2003年6月	2003年9月	2004年1月	2004年6月	2005年1月
2005年6月	2005年12月	2006年6月	2006年12月	2007年6月
2007年12月	2008年6月	2008年12月	2009年6月	2009年12月

六级历年真题（2001-2009）