[单项选择]Many geologists theorize that the trail of volcanic craters and cinder cones along the Snake River plain of southern Idaho was produced as the North American continent slid westward over a stationary "plume," a vertical channel through which molten rock rose intermittently from the Earth’s core to burst through its crust.
Which of the following, if true, tends to support the geologists’ theory of how the trail was produced
A. The largest craters and cinder cones are on the eastern margin of the trail.
B. The most violent volcanic activity apparently occurred at the western margin of the trail.
C. The craters and cinder cones are evenly spaced throughout the extent of the trail.
D. The newest craters and cinder cones are on the eastern margin of the trail.
E. (E) The craters grid cinder cones on the western margin of the trail generally took longer to form than did those on the eastern margin.

[单项选择]Most geologists believe oil results from chemical transformations of hydrocarbons derived from organisms buried under ancient seas. Suppose, instead, that oil actually results from bacterial action on other complex hydrocarbons that are trapped within the Earth. As is well known, the volume of these hydrocarbons exceeds that of buried organisms. Therefore, our oil reserves would be greater than most geologists believe.
Which of the following, if true, gives the strongest support to the argument above about our oil reserves
A. Most geologists think optimistically about the Earth’s reserves of oil.
B. Most geologists have performed accurate chemical analyses on previously discovered oil reserves.
C. Ancient seas are buried within the Earth at many places where fossils are abundant.
D. The only bacteria yet found in oil reserves could have leaked down drill holes from surface contaminants.
E. (E) Chemical transformations reduce the volume of buried hydrocarbons derived from organisms by roughly the same proportion as bacterial action reduces the volume of other complex hydrocarbons.

[单项选择]Geologists suggested that the region might in fact be more susceptible to earthquakes than ______.
A. previously been believed
B. it had previously believed
C. did it previously believe
D. had previously been believed

[填空题]Geologists believe that oil and coal are composed of organic molecules______(因为它们本身来自于生物).

[简答题]Most geologists believe that the earth’s primordial ocean was made of ______ from volcanic eruptions.

[单项选择]Some geologists argue that if oil is as common in unsampled areas of the world as it is in those already sampled, our current estimate of reserves that exist underground must be multiplied by a factor of 10,000. From this we can conclude that we can meet the oil needs of the entire world for at least five centuries, even assuming that future consumption grows at an accelerating rate.
To reach the stated conclusion, the author must assume which of the following
A. It is possible to recover the oil contained in unexplored areas of the world.
B. The consumption rate for oil will not grow rapidly.
C. Oil will remain an important energy source for at least 500 years.
D. The world will achieve and maintain zero population growth.
E. (E) New technology will make oil discovery and drilling more feasible than ever before.

[填空题]S5. Geologists think that the rock deep in the earth is_______________________.

[单项选择]

When people search online, they leave a trail that remains stored on the central computers of firms such as Google, Yahoo and Microsoft. Analyzing what we’re looking for on the Web can offer a remarkable (51) into our anxieties and enthusiasms,
UK writer and Internet expert John Battelle wrote on his blog, "This can tell us (52) things about who we are and what we want as a (53) ." Google’s experimental service Google Trends, for example, compares the numbers of people searching for different words and phrases from 2004 to the present. According to these graphs, sometimes people’s interests are obviously (54) the news agenda: when the Spice Girls announce a reunion, there’s an immediate (55) to find out more about them. Other results are strikingly seasonal: people go shopping online for coats in winter and short pants in summer.
The most fascinating possibility is that search data might
A. extraordinary
B. obvious
C. mysterious
D. sensitive

[单项选择]Who’s to blame The trail of responsibility goes beyond poor maintenance of British railways, say industry critics. Stingy governments — both Labor and Tory —have cut down on investments in trains and rails. In the mid-1990s a Conservative government pushed through the sale of the entire subsidy-guzzling rail network. Operating franchises were parceled out among private companies and a separate firm, Railtrack, was awarded ownership of the tracks and stations. In the future, the theory ran back then, the private sector could pay for any improvements— with a little help from the state—and take the blame for any failings.
Today surveys show that travelers believe privatization is one of the reasons for the railways’ failures. They ask whether the pursuit of profits is compatible with guaranteeing safety. Worse, splitting the network between companies has made coordination nearly impossible. "The railway was torn apart at privatization and the structure that was put in place was ..
A. trace the failure of Britain’s rail network to its defective origin
B. remind people the glorious past of Britain’s railway
C. argue for Britain’s rail network
D. call for impartiality in assessing the situation

[填空题]Several newspapers are on trail of some corrupt politicians.

[填空题]The Cabot Trail in the Kejumkujik National Park is famous for its scenic drive.

[填空题]Many plant foods provide both many vitamins and minerals of very few calories.