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Passage 2
Questions 6 to 10 are based on the following passage:
When aluminum was first produced about a hundred and fifty years ago, it was
so difficult to separate form the ores in which it was found that its price was
higher than that of gold. The price remained high until a new process was
discovered for refining the metal with the aid of electricity approximately
three quarters of a century later. The new method was so much cheaper that
aluminum because practical for many purposes, one of which was making pots and
pans.
Aluminum is lightweight, rustproof and easily shaped into different forms. By
mixing it with other metals, scientists have been able to produce a variety of
alloys, some of which have the strength of steel but weigh only one third as
much.
Today, the uses of aluminum are innumerable. Perhaps its most important use
is in transportation. Aluminum is found in the engine of automobiles, in the
hulls of boats. It is also used in many parts of airplanes. In fact, the huge
“airbus” planes would probably never have been produced if aluminum did not
exist. By making vehicles lighter in weight aluminum has greatly reduced the
amount of fuel needed to move them, Aluminum is also being used extensively in
the building industry in some countries.
Since aluminum is such a versatile (多用的) metal, it is fortunate that bauxite
(铝土矿), which is one of its chief sources, is also one of the earth’s most
plentiful substances. As the source of aluminum is almost inexhaustible, we can
expect that more and more uses will be found for this versatile metal.
6. The price of aluminum was sharply reduced when people discovered a new
refining process with the aid of .
A. wind B. solar energy C. hydraulic power D. electricity
7. Aluminum is .
A. lightweight, rustproof but not easily shaped into different forms
B. heavyweight, rustproof and easily shaped into different forms
C. lightweight, rustproof and easily shaped into different forms
D. lightweight and easily shaped into different forms but it is easy to
become rusty
8. Which of the following is NOT true?
A. Aluminum is widely used in transportation.
B. Aluminum is also used in many parts of airplanes.
C. Aluminum is being used extensively in the building industry.
D. Aluminum is not used in its pure form.
9. Aluminum is found on earth mostly in the form of .
A. pure metal B. bauxite C. gold D. liquid
10. What is the passage talking about?
A. The features of aluminum and its functions. B. The process of
aluminum.
C. The discovery of aluminum. D. The promising future of aluminum.
