题目内容

Many people consider the wider use of biofuels a promising way of reducing the amount of surplus carbon dioxide (CO2n) being pumped into the air by the world’s mechanized transport. The theory is that plants such as sugar cane, maize (corn, to Americans), oilseed rape and wheat take up CO2 during their growth, so burning fuels made from them should have no net effect on the amount of that gas in the atmosphere.
Theory, though, does not always translate into practice, and just as governments have committed themselves to the greater use of biofuels, questions are being raised about how green this form. of energy really is. The latest comes from the International Council for Science (ICSU) based in Paris.
The ICSU report concludes that, so far, the production of biofuels has aggravated rather than ameliorated global warming. In particular, it supports some controversial findings published in 2007 by Paul Crutzen of the Max Planck Institute for Chemistry in Germany. Dr. Crutzen concluded that most analyses had underestimated the importance to global warming of a gas called nitrous oxide (N2nO). The amount of this gas released by farming biofuel crops such as maize and rape probably negates by itself any advantage offered by reduced emissions of CO2n.
Although N2nO is not common in the Earth’s atmosphere, it is a more potent greenhouse gas than CO2n and it hangs around longer. The result is that, over the course of a century, its ability to warm the planet is almost 300 times that of an equivalent mass of CO2n.
N2nO is made by bacteria that live in soil and water and, these days, their raw material is often the nitrogen-rich fertiliser that modern farming requires. Since the 1960s the amount of fertiliser used by farmers has increased sixfold, and not all of that extra nitrogen ends up in their crops. Maize, in particular, is described by experts in the field as a “nitrogen-leaky” plant because it has shallow roots and takes up nitrogen for only a few months of the year. This would make maize (which is one of the main sources of biofuel) a particularly bad contributor to global N2nO emissions.
But it is not just biofuels that are to blame. The ICSU report suggests N2nO emissions in general are probably more important than had been realised. Previous studies, including those by the International Panel on Climate Change (IPCC), a United Nations-appointed body of experts, may have miscalculated their significance — and according to Adrian Williams of Cranfield University, in Britain, even the IPCC’s approach suggests that the global-warming potential of most of Britain’s annual crops is dominated by N2nO emissions.
Biofuels are appreciated by governments because

A. burning biofuels does not add CO2n to the atmosphere.
B. biofuels can slow down the pace of global warming.
C. biofuels is a promising and profitable form. of green energy.
D. burning biofuels discharges less N2nO than burning oils.

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When Olson say “We’re really there for when the processes fall down” (Line 4, Para. 5), she means that

A. they will provide help whenever taxpayers make claims.
B. they will get involved in the normal appeals process.
C. they will offer counseling when citizen calls.
D. they will give help when procedural problems occur.

The word “languish” (Line 4, Para. 4) is closest in meaning to

A. wither.
B. abort.
C. lose vigor.
D. lose appeal.

Another factor in the display of art objects (concerns their continued preservation). Because of the sensitivity of some of the materials (used in their creation), it is necessary to control (within narrow limits) the temperature, humidity, and lighting (

A. concerns their continued preservation
B. used in their creation
C. within narrow limits
D. which

Part A
Directions: Read the following four texts. Answer the questions below each text by choosing A, B, C or D. (40 points)
In the last ten years, the Internet has opened up incredible amounts of information to ordinary citizens. But using the Internet can he like walking into a library where the books are all lying on the floor in piles. While tools like Google allow some structured search, much of the data from such searches is outdated or of questionable value. Some web enthusiasts have taken up the task of organizing information through a democratic means that only the Internet allows: an encyclopedia of the people, by the people, and completely free to copy and distribute.
This ‘people’s encyclopedia’ of the Web — a free site called Wikipedia — has provided a unique solution by inviting individuals to participate in the process of rationalizing and updating web content. At the heart of this movement are wikis, web sites that allow users to directly edit any web page with one click of the mouse.
Wikipedia — the largest example of these collaborative efforts — is a functioning, user-contributed online encyclopedia that has become a popular and highly regarded reference in just three years of existence. The goal of Wikipedia was to create an encyclopedia that could he shared and copied freely while encouraging people to change and improve the content. Each and every article has an “Edit this page” button, allowing anyone, even anonymous passersby, to add or delete any content on the page. It seems like a recipe for disaster and chaos, but it has produced surprisingly credible content that has been evaluated and revised by the thousands of international visitors to the site. For many, it finally realizes the original concept of World Wide Web creator Tim Berners-Lee — an online environment where people not only browse content, but freely and actively exchange information.
The Wikipedia project was started by Jimmy Wales, head of Internet startup Bomis.com, after his original project for a volunteer, hut strictly controlled, free encyclopedia ran out of money and resources after two years. Editors with PhD degrees were at the helm of the project then, but it produced only a few hundred articles. Not wanting the content to languish, Wales placed the pages on a wiki website in January 2001 and invited any Internet visitors to edit or add to the collection.
The site became a runaway success in the first year and gained a loyal following, generating over 20,000 articles and spawning over a dozen language translations. After two years, it had 100,000 articles, and in April 2004, it exceeded 250,000 articles in English and 600,000 articles in 50 other languages. Over 2,000 new articles are added each day across all the various languages. And according to website rankings at Alexa.com, it has become more popular than traditional online encyclopedias such as Britannica.com and is one of the top 600 most heavily visited websites on the internet.
The author called Wikipedia ‘people’s encyclopedia’ because

A. it is accessible to all the passersby.
B. it can be edited by everyone.
C. it is run by ordinary people.
D. it is built to the taste of common citizens.

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