[单项选择]The greatest difficulty cognitive scientists are now unable to solve is ______.
A. learning about how people solved problems
B. asking people to describe what they have in their minds
C. using computers to stimulate thought
D. recording mental processes of problem-solving

[单项选择]British political scientists once had difficulty understanding how the unbalancing effects of affording greater representation to the wealthy was once the means of preserving the______of the commonwealth.
A. (A) character
B. (B) equipoise
C. (C) affluence
D. (D) discontent
E. (E) rectitude

[单项选择]The greatest task facing agricultural scientists in this region is the __________ of an adaptable farming system.
A. determination
B. distribution
C. discipline
D. evolution

[单项选择]According to the passage, what can scientists do now with the genetic testing technology

[单项选择]— Did you have difficulty finding John's house —Not really. John had given us good directions and we ______find it.
A. would
B. could
C. had to
D. were able to

[单项选择]Scientists in the world are expected to find a(n) _____ to the problem of over population.
A. reply
B. solution
C. response
D. answer

[单项选择]Scientists are eager to talk with other scientists working on similar problems．
A. 科学家热衷于与从事类似课题研究的其他科学家交流。
B. 科学家更容易与其他科学家谈话来解决相同的问题。
C. 科学家很乐意在解决类似问题时同其他科学家交流。
D. 科学家更容易就雷同的问题与其他科学家交谈。

[单项选择]Medical scientists believe that
A. tests have been designed to settle the cholesterol dispute
B. drugs have been tested to reduce the amount of the substance in blood
C. low cholesterol foods or anti-cholesterol drugs or both can reduce the chance of a heart attack
D. none of the statements mentioned above is correct

[单项选择]The Cognitive Approach teachers believe language learning is ______ not simply the forming of habits.
A. a process
B. recognition
C. communication
D. presentation

[单项选择]The Cognitive Approach holds that students’ mistakes are ______ in the creative use of language.
A. useful
B. understandable
C. unavoidable
D. reasonable

[单项选择]One of the consequences of advanced cognitive ability has been the emergence of cultural life.
A. commendable
B. compiling
C. perceptive
D. pertinent

[单项选择]What links cognitive development to the needs of society
A. Practical purpose.
B. Natural human cognitive development.
C. Language.
D. Sending or receiving messages.

[单项选择]The scientists began to accumulate dat


A. A． collectB. handleC. analyzeD. investigate

[单项选择]

Scientists have established that influenza viruses taken from man can cause the disease in animals. In addition, man can catch the disease from animals. In fact, a great number of wild birds seem to carry the virus without showing an evidence of illness. Some scientists concluded that a large family of influenza viruses may have evolved in the bird kingdom, a group that has been on the earth 100 million years and is able to carry the virus without contracting the disease. There is even convincing evidence to show that virus strains are transmitted from place to place and from continent to continent by migrating birds.
It’s known that two influenza viruses can recombine when both are present in an animal at the same time, the result of such recombination is a great variety of strains containing different H and N spikes. This raises the possibility that a human influenza virus can recombine with an influenza virus from a low animal to produce an entirely new s
A. A type of wild pig
B. diseased lower animals
C. a group of migrating birds
D. a variety of means