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Scattered through the seas of the world are billions of tons of small plants
and animals called plankton. Most of these plants and animals are too small for
the human eye to see. They drift about lazily with the currents, providing a
basic food for many larger animals. Plankton has been described as the
equivalent of the grasses that grow on the dry land continents, and the
comparison is an appropriate one. In potential food value however, plankton far
outweighs that of the land grasses. One scientist has estimated that while
grasses of the world produce about 49 billion tons of valuable carbohydrates
each year. The sea’s plankton generates more than twice as much.
Despite its enormous food potential, little effort was made until recently to
farm plankton as we farm grasses on land. Now marine scientists have at last
begun to study this possibility, especially as the sea’s resources loom even
more important as a means of feeding an expanding world population.
No one yet has seriously suggested that “planktonburgers” may soon become
popular around the world. As a possible farmed supplementary food source,
however, plankton is gaining considerable interest among marine scientists.
One type of plankton that seems to have great harvest possibilities is a tiny
shrimplike creature called krill. Growing to two or three inches long, krill
provide the major food for the giant blue whale, the largest animal ever to
inhabit the Earth. Realizing that this whale may grow 100 feet and weigh 150
tons at maturity, it is not surprising that each one devours more than one ton
of krill daily.
Krill swim about just below the surface in huge schools sometimes miles wide,
mainly in the cold Antarctic. Because of their pink color, they often appear as
a solid reddish mass when viewed from a ship or from the air. Krill are very
high in food value. A pound of these crustaceans contains about 460
calories—about the same as shrimp or lobster, to which they are related.
If the krill can feed such huge creatures as whales, many scientists reason,
they must certainly be contenders as new food source for humans.
1.Which of the following best portrays the organization of the passage?
A.The author presents the advantages and disadvantages of plankton as a food
source.
B.The author quotes public opinion to support the argument for farming
plankton.
C.The author classifies the different food sources according to amount of
carbohydrate.
D.The author makes a general statement about plankton as a food source and
then moves to a specific example.
2.According to the passage, why is plankton regarded to be more valuable than
land grasses?
A.It is easier to cultivate.
B.It produces more carbohydrates.
C.It does not require soil.
D.It is more palatable.
3.Why does the author mention “planktonburgers”?
A.To describe the appearance of one type of plankton.
B.To illustrate how much plankton a whale consumes.
C.To suggest plankton as a possible food sources.
D.To compare the food values of beef and plankton.
4.What is mentioned as one conspicuous feature of krill?
A.They are the smallest marine animals.
B.They are pink in color.
C.They are similar in size to lobsters.
D.They have grass like bodies.
5.The author mentions all of the following as reasons why plankton could be
considered a human food source except that it is ___.
A.high in food value.
B.in abundant supply in the oceans.
C.an appropriate food for other animals.
D.free of chemicals and pollutants.
The discovery of the Antarctic not only proved one of the most interesting of all geographical adventures, but created what might be called “the heroic age of Antarctic exploration”. By their tremendous heroism, men such as Shakleton, Scott, and Amundsen caused a new continent to emerge from the shadows, and yet that heroic age, little more than a century old, is already passing. Modern science and inventions are revolutionizing the endurance, future journeys into these icy wastes will probably depend on motor vehicles equipped with caterpillar traction rather than on the dogsthat earlier discoverers found so invaluable and hardly comparable.
Few realize that this Antarctic continent is almost equal in size to South America, and enormous field of work awaits geographers and prospectors. The coasts of this continent remain to be accurately charted, and the maping of the
whole of the interior presents a formidable task to the cartographers who undertake the work. Once their labors are completed, it will be possible to prospect the vast natural resources which scientists believe will furnish one of the largest treasure hoards of metals and minerals the world has yet known, and almost inexhaustible sources of copper,coal, uranium, and many other ores will become available to man. Such discoveries will usher in an era of practical exploitation of the Antarctic wastes.
The polar darkness which hides this continent for the six winter months will be defeated by huge batteries of light, and make possible the establishing of air-fields for the future inter-continental air services by making these areas as light as day. Present flying routes will be completely changed, for the Antarctic refueling bases will make flights from Australia to South America comparatively easy over the 5,000 miles journey.
The climate is not likely to offer an insuperable problem, for the explorer
Admiral Byrd has shown that the climate is possible even for men completely
untrained for expeditions into those frozen wastes. Some of his parties were men
who had never seen snow before, and yet he records that they survived the rigors
of the Antarctic climate comfortably, so that, provided that the appropriate
installations are made, we may assume that human beings from all countries could
live there safely. Byrd even affirms that it is probably the most healthy
climate in the world, for the intense cold of thousands of years has sterilize
this continent, and rendered it absolutely germfree, with the consequences that
ordinary and extraordinary sickness and diseases from which man suffers in other
zones with different climates are here utterly unknown. There exist no problems
of conservation and preservation of food supplies, for the latter keep
indefinitely without any signs of deterioration; it may even be that later
generations will come to regard the Antarctic as the natural storehouse for the
whole world.
Plans are already on foot to set up permanent bases on the shores of this
continent, and what so few years ago was regarded as a “dead continent” now
promises to be a most active center of human life and endeavor.
1.When did man begin to explore the Antarctic?
A.About 100years ago.
B.In this century.
C.At the beginning of the 19th century.
D.In 1798.
2.What must the explorers be, even though they have modern equipment and
techniques?
A.Brave and tough
B.Stubborn and arrogant.
C.Well-liked and humorous.
D.Stout and smart.
3.The most healthy climate in the world is___.
A.in South America.
B.in the Arctic Region.
C.in the Antarctic Continent.
D.in the Atlantic Ocean.
4.What kind of metals and minerals can we find in the Antarctic?
A.Magnetite, coal and ores.
B.Copper, coal and uranium.
C.Silver, natural gas and uranium.
D.Aluminum, copper and natural gas.
5.What is planned for the continent?
A.Building dams along the coasts.
B.Setting up several summer resorts along the coasts.
C.Mapping the coast and whole territory.
D.Setting up permanent bases on the coasts.
Part III Cloze
Directions: There are twenty blanks in the following passage. For each blank there are four choices. Choose the one that best fits into the passage and then marks your answer on the Answer Sheet.
What makes a child speak a language has long been a puzzle to linguists. 61 speaking, there are two schools of linguists, both of whom try to explain 62 a child picks up a language so easily. The fact that a child picks a language 63 is 64 : At one year old, a child is able to say “bye-bye”; at two, he is able to
use fifty; by there he begins to 65 tenses. The famous American linguist Noam Chomsky 66 that human being have a sort of built-in system for language use, and that the 67 is 68 . Children are not taught language 69 they are taught arithmetic. Other linguists, 70 , hold the view that a child learns 71 of his
language from the hints in the environment. 72 , theorists of both schools 73 that there is a biological basis for language use. The 74 is which is more important, the inner ability or the environment. This is certainly a field 75 to be explored. Researchers from both schools are busy finding evidence to 76 their own theory, but 77 side is persuading the other.
It seems that in order to 78 why a child learns a language so easily, we have to 79 the joint efforts of both schools. Some linguist, like De Villiers, has recognized the value of cooperation, and 80 linguists of both sides to work together.
61. A. Surprisingly B. Personally C. Properly D. Roughly
62. A. that B. when C. why D. how
63. A. independently B. naturally C. without help D. with ease
64. A. confusing B. surprising C. questioned D. suspected
65. A. master B. study C. have D. get
66. A. doubts B. believes C. realizes D. criticizes
67. A. help B. teacher C. environment D. hint
68. A. quite essential B. very important C. not necessary D. only
secondary
69. A. as B. for C. when D. though
70. A. in particular B. as a result C. however D. therefore
71. A. a little B. some C. nothing D. most
72. A. Before B. From now on C. Just now D. By now
73. A. suspect B. disagree C. agree D. realize
74. A. case B. argument C. problem D. question
75. A. waiting B. planning C. never D. unlikely
76. A. provide B. create C. supply D. support
77. A. not a B. one C. neither D. either
78. A. find out B. rule out C. search for D. look for
79. A. get rid of B. trust in C. rely on D. persist in
80. A. ordered B. criticized C. challenged D. urged
