填空题

The oceans have always served as a sink for carbon dioxide, but the burning of fossil fuels since the beginning of the industrial revolution, especially over the last 40 years, has given them more than they can (36) absorb. The result is that the oceans are becoming acid—a change in the (37) balance that threatens the oceans’ web of life.
In earth’s history, there have been many (38) of acidification, mainly from volcanic eruptions (火山喷发). According to a new research review by pale oceanographers at Columbia University, published in Science, the oceans may be (39) acid far faster than at any time in the past 300 million years.
Changing something as (40) as the PH of seawater has profound effects. Increased acidity attacks the shells of shellfish and the skeletal foundation of corals (珊瑚), dissolving the calcium carbonate (硝酸钙) they’re made of. Coral reefs are among the most diverse ecosystems on the planet. Ocean acidification (41) the corals and every other (42) that makes its living on the reefs.
The authors tried to determine which past acidification events (43) the best comparison to what is happening now. The closest analogies are disastrous events, often associated with intense volcanic activity resulting in major extinctions. The difference is that those events (44) thousands of years. We have acidified the oceans in a matter of decades, with no signs that we have the political will to slow, much less halt, the (45) .
A．absolutely
B．animals
C．changing
D．chemical
E．covered
F．episodes
G．fundamental
H．offer
I．process
J．safely
K．species
L．transmitted
M．threatens
N．turning
O．urgent

【参考答案】

J
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A．Because machines reduced the price and made cigarettes popular. B．Because cigarette industry only began to develop in the 1870’s. C．Because factories produced more cigarettes than before. D．Because people began to accept smoking as a habit.
A．Because machines reduced the price and made cigarettes popular.
B．Because cigarette industry only began to develop in the 1870’s.
C．Because factories produced more cigarettes than before.
D．Because people began to accept smoking as a habit.
填空题
In most parts of the world, the relation between population and resources is already unfavorable and will probably become even more unfavorable in the future. This growing poverty constitutes a (26) menace not only to peace, but also to democratic institutions and personal liberty. An (27) relationship between numbers and resources tends to make the earning of a living almost intolerably difficult. The individual (28) work long hours for little pay. No surplus of accumulated purchasing power stands between him and the cruelty of (29) nature. Democracy is. among other things, the ability to say no to the boss. But a man cannot say no to the boss, unless he is sure of being able to eat when the boss’s favor has been (30) . And he cannot be certain of his next meal unless he owns the means of producing enough wealth for his family to live on, or has been able to accumulate a surplus out of past (31) , or has a chance of moving to virgin territories, where he can (32) . In an overcrowded country, very few people own enough to make them financially independent; very few are in a position to accumulate purchasing power; and there is no free land. Moreover, in any country where population (33) hard upon natural resources, the general economic situation (34) be so uncertain. As a result, government control of capital and labor, production and consumption becomes (35) . It is no accident that the 20th century should be the century of highly centralized governments and dictatorships; it had to be so for the simple reason that the 20th century is the century of global overcrowding.
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