题目内容
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Why do forests in many parts of the world slowly disappear？
A．New trees are not looked after properly.
B．Many trees have been cut down by man.
C．Man has not paid enough attention to planting trees.
D．All of the above.
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In an early survey conducted in 1888, a billion and a half people inhabited the earth. Now, the population exceeds five billion and is growing fast—by the staggering figure of 90 million in 1988 alone. This means that the world must accommodate a new population roughly equal to that of the United States and Canada every three years! Even though the rate of growth has begun to slow down, most experts believe the population size will still pass eight billion during the next 50 years.
So why is this huge Increase in population taking place？ It is really due to the spread of the knowledge and practice of what is becoming known as "Death Control". You have no doubt heard of the term "Birth Control"—"Death Control" is something rather different. It recognizes the work of the doctors and scientists who now keep alive people who, not very long ago, would have died of a variety of then incurable diseases. Through a wide variety of technological innovations that include farming methods and sanitation, as well as the control of these deadly diseases, we have found ways to reduce the rate at which we die—creating a population explosion. We used to think that reaching seventy years old was a remarkable achievement, but now eighty or even ninety is becoming recognized as the normal life-span for humans. In a sense, this represents a tremendous achievement for our species. Biologically this is the very definition of success and we have undoubtedly become the dominant animal on the planet. However, this Success is the very cause of the greatest threat to mankind.
Man is constantly destroying the very resources which keep him alive. He is destroying the balance of nature which regulates climate and the atmosphere, produces and maintains healthy soils, provides food from the seas, etc. In short, by only considering our needs of today, we are ensuring there will be no tomorrow.
An understanding of man's effect on the balance of nature is crucial to be able to find the appropriate remedial action. It is a very common belief that the problems of the population explosion are caused mainly by poor people living in poor countries who do not know enough to limit their reproduction. This is not true. The actual number of people in an area is not as important as the effect they have on nature. Developing countries do have an effect on their environment, but it is the populations of richer countries that have a far greater impact on the earth as a whole.
The birth of a baby in, for example, Japan, imposes more than a hundred times the amount of stress on the world's resources as a baby in India. Most people in India do not grow up to own cars or air-conditioners—nor do they eat the huge amount of meat and fish that the Japanese child does. Their life-styles do not require vast quantities of minerals and energy. Also, they are aware of the requirements of the land around them and try to put something back into nature to replace what they take out.
For example, tropical forests are known to be essential to the balance of nature yet we are destroying them at an incredible rate. They are being cleared not to benefit the natives of that country, but to satisfy the needs of richer countries. Central American forests are being destroyed for pastureland to make pet food in the United States cheaper; in Papua New Guinea, forests are destroyed to supply cheaper cardboard packaging for Japanese electronic products; in Burma and Thailand, forests have been destroyed to produce more attractive furniture in Singapore and Japan. Therefore, a rich person liv
A．to put forward the argument that world population has to be reduced.
B．to give a brief history of the growth in world population.
C．to emphasize how quickly the world population is rising.
D．to stress how large the world population is now.
A．a and b
B．a and c
C．c and d
D．b and d
What scientists can do right now is make good maps of fault zones and (7)_____ out which ones are probably due (8)_____ a rupture. And they can make forecasts. A forecast might say that, over a certain number of years, there is a certain (9)_____ of a certain magnitude earthquake in a (10)_____ spot. And that you should fix your house to its foundation and glue the water heater to the wall.
Turning forecasts into predictions—"a magnitude 7 earthquake is (11)_____ here three days from now"—may be impossible, but scientists are doing everything they can to solve the (12)_____ of earth quakes. They break rocks in laboratories, studying how stone (13)_____ under stress. They hike (14)_____ ghost forests where dead trees (15)_____ of long-ago tsunamis. They make maps of unsecured, balanced rocks to see where the ground has (16)_____ in the past and how hard. They dig ditches across faults, searching for the active trace. They have wired up fault zones with so many sensors it is (17)_____ the Earth is a patient (18)_____ intensive care.
(19)_____, we tell ourselves—trying hard to be persuasive—there must be some way to (20)_____ order and criterion on all that untrustworthy ground.
A．birth
B．rise
C．ground
D．way
A．The writer did not give his explanation in detail.
B．The rain forests' survival is questionable.
C．It will become warmer and warmer with the depletion of rain forests.
D．Many wild animals and beasts will extinct as result of the depletion of rain forests.
Why did Wilson regard "the greatest extinction since the end of the age of dinosaurs" to be the depletion of rain forest areas？
A. The writer did not give his explanation in detail.
B. The rain forests' survival is questionable.
C. It will become warmer and warmer with the depletion of rain forests.
D. Many wild animals and beasts will extinct as a result of the depletion of rain forests.
Why are buses critical to realizing the hybrid dream of higher efficiency？
A．Buses are a major source of pollution.
B．A single bus saves much more gas than a single car.
C．Buses carry more passengers.
D．New buses produce less harmful material.
Excuse me. If your call' s not too urgent, do you mind ______ mine first？
A．I make
B．if I make
C．me to make
D．that I make
Why do people in the USA. feel shopping is a breeze？
A．The price is very cheap.
B．The products are good.
C．The signs of departments are clear.
D．The departments are large.
