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Where Have All the Frogs Gone

 

In the 1980s, scientists around the world began to notice something strange: Frogs were disappearing. More recent research has shown that many kinds of amphibians (两栖动物) are declining or have become extinct. They have been around for a long time—over 350 million years. Why are they dying out now
Scientists are seriously concerned about this question. First of all, amphibians are an important source of scientific and medical knowledge. By studying amphibians, scientists have learned about new substances that could be very useful for treating human diseases. Further research could lead to many more discoveries, but that will be impossible if the amphibians disappear.
The most serious aspect of amphibian loss, however, goes beyond the amphibians themselves. Scientists are beginning to think about what amphibian decline means for the planet as a whole. If the earth is
A. poisonous gases
B. air pollution
C. water leakage
D. radiation

[单项选择]

 

In the 1980s, scientists around the world began to notice something strange: Frogs were disappearing. More recent research has shown that many kinds of amphibians (两栖动物) are declining or have become extinct. They have been around for a long time—over 350 million years. Why are they dying out now
Scientists are seriously concerned about this question. First of all, amphibians are an important source of scientific and medical knowledge. By studying amphibians, scientists have learned about new substances that could be very useful for treating human diseases. Further research could lead to many more discoveries, but that will be impossible if the amphibians disappear.
The most serious aspect of amphibian loss, however, goes beyond the amphibians themselves. Scientists are beginning to think about what amphibian decline means for the planet as a whole. If the earth is
A. it has been threatened by frogs
B. it is losing its habitat
C. a disease has been killing its eggs
D. it can’t bear the cold of winter

[单项选择]

 

In the 1980s, scientists around the world began to notice something strange: Frogs were disappearing. More recent research has shown that many kinds of amphibians (两栖动物) are declining or have become extinct. They have been around for a long time—over 350 million years. Why are they dying out now
Scientists are seriously concerned about this question. First of all, amphibians are an important source of scientific and medical knowledge. By studying amphibians, scientists have learned about new substances that could be very useful for treating human diseases. Further research could lead to many more discoveries, but that will be impossible if the amphibians disappear.
The most serious aspect of amphibian loss, however, goes beyond the amphibians themselves. Scientists are beginning to think about what amphibian decline means for the planet as a whole. If the
A. in any stream they can find
B. in places without UV light
C. only on sand
D. only in the right conditions

[单项选择]

In the 1980s, scientists around the world began to notice something strange: Frogs were disappearing. More recent research has shown that many kinds of amphibians (两栖动物) are declining or have become extinct. They have been around for a long time—over 350 million years. Why are they dying out now
Scientists are seriously concerned about this question. First of all, amphibians are an important source of scientific and medical knowledge. By studying amphibians, scientists have learned about new substances that could be very useful for treating human diseases. Further research could lead to many more discoveries, but that will be impossible if the amphibians disappear.
The most serious aspect of amphibian loss, however, goes beyond the amphibians themselves. Scientists are beginning to think about what amphibian decline means for the planet as a whole. If the earth is becoming u
A. knowledge about fatal human diseases
B. knowledge about air and water pollution
C. a chance to discover new medicines
D. an opportunity to detect poisonous gases

[单项选择]

Where Have All the Frogs Gone
In the 1980s, scientists around the world began to notice something strange: Frogs were disappearing. More recent research has shown that many kinds of amphibians (两栖动物) are declining or have become extinct. They have been around for a long time - over 350 million years. Why are they dying out now
Scientists are seriously concerned about this question. First of all, amphibians are an important source of scientific and medical knowledge. By studying amphibians, scientists have learned about new substances that could be very useful for treating human diseases. Further research could lead to many more discoveries, but that will be impossible if the amphibians disappear.
The most serious aspect of amphibian loss, however, goes beyond the amphibians themselves. Scientists are beginning to think about what amphibian decline means for the planet as a whole. If the earth is becoming unlivable for amphibians, is it also becoming
A. knowledge about fatal human diseases.
B. knowledge about air and water pollution.
C. a chance to discover new medicines.
D. an opportunity to detect poisonous gases.

[单项选择]Think of all the criminals who have killed, all the soldiers who have killed; consider the mass murder of Jews in Nazi Germany. Is there something inside human beings that allows us to take part in this sort of violence, or were these people swept along by the situation
Stanley Milgram, a New York psychologist, designed an experiment to find answers to this question, paying adult males four and a half dollars to act the role of "teacher" in a complicated experiment. The "teachers" were to ask questions of a "learner", a middle-aged man in another room. If the learner gave an incorrect answer, the teacher was instructed to turn a knob to send an electric current to the learner’s chair. There were thirty positions on the control knob, with the shocks ranging from 15 to 450 volts, the last position marked "Danger: Severe Shock". The teachers were told to increase the severity of the shock with each incorrect response.
With the first few shocks, the learner could be heard over t
A. prove that all men are violent
B. discuss historical incidences of violence
C. describe the Milgram experiment
D. show how shock affects the ability to learn