更多"Scientists have spent years________"的相关试题:
[单项选择]Scientists have spent years into the effects of certain chemicals on the human brain, but with no result.（）
A. studying
B. researching
C. investigating
D. inspecting
[单项选择]Scientists wilt have to ______ new methods of increasing the world's food supply in order to feed more hungry people.
A. catch up with
B. come up with
C. keep up with
D. put up with
[单项选择]Scientists have already found problems that associated（）living in the ocean are nearly the same as those of living in outer space.
A. to
B. of
C. with
D. at
[单项选择]Social scientists have recently become greatly interested in space because ______.
A. space industrialization will create new markets and more jobs on Earth
B. space exploration will be harmful to man
C. space colonization is near at hand
D. otherwise technologists will catch the opportunity to go to space
[单项选择]The passage probably implies that scientists have been______.
[单项选择]Scientists have traditionally (classified) plants by (grouping them) according to similarities in their overall (appear), their internal structure, and the form of their (reproductive) organs.
A. classified
B. grouping them
C. appear
D. reproductive
[单项选择]Scientists have acknowledged that to interpret an animal's thought processes in a sound manner requires a heavy dose of-------from our own mental patterns, which we access------.
A. (A) estimation...vicariously
B. (B) calculation...egotistically
C. (C) guesswork...methodically
D. (D) inference...introspectively
E. (E) skepticism...analogously
[单项选择]Scientists have warned that penguins in the Antarctic could be very________to changes in climate and could be threatened by any long-term temperature shifts.
A. superstitious
B. acceptable
C. suspicious
D. susceptible
[单项选择]What social scientists have long felt puzzled about
A. The mortality rate can not be predicted.
B. The death toll remained stable year after year.
C. A quota for each type of death has not come into being.
D. People lost their lives every year for this or that reason.
[单项选择]Chinese and Russian scientists have reposed that in places______stress is building up, the radon levels of the water build up too.
A. what
B. that
C. which
D. where
[单项选择]British scientists have found how to diagnose the disease, which causes loss of memory and personality change.
A. control
B. determine
C. prevent
D. treat
[单项选择]Experiments by scientists have shown that when people evaluate individuals on certain attributes,______.
A. they observe the principle that beauty is only skin-deep
B. they do not usually act according to the views they support
C. they give ordinary-looking persons the lowest rating
D. they tend to base their judgment on the individual’s accomplishment
[单项选择]Scientists have developed glass fibers as thin as human hair which are designed to carry light signals.
A. 科学家发展出一种玻璃纤维，轻得像人的头发丝一样，可以用来设计轻型的信号装置。
B. 科学家制造出一种玻璃纤维，比人的头发丝还细，这种设计是用来传递光信号的
C. 科学家开发出像人的头发一样细的玻璃纤维来传输光信号。
D. 科学家研制出跟人的头发丝似的玻璃纤维，用在光导信号的设计上。
[单项选择]The social scientists have long felt confused about the fact that______.
A. 2,500 people accidentally commit suicide every year
B. the death rates remained stable year after year
C. a quota for each type of death has not established
D. people lost their lives every year for this or that reason
[单项选择]According to the passage, scientists have positively confirmed that the brains of narcoleptics differ from those of normal brains in which of the following ways
A. (A) Narcoleptic brains tend to remove degenerative tissue at a more prolific rate than that of nonnarcoleptics.
B. (B) Narcoleptics are less responsive to drugs which treat neural autoimmune dysfunction than are nonnarcoleptics.
C. (C) Nonnarcoleptics do not possess the same neurological immune antigens as narcoleptics.
D. (D) Neurons that control muscle tone are damaged in the brains of narcoleptics, but not in those of non-narcoleptics.
E. (E) Narcoleptics experience greater neural degeneration as a result of aging than do nonnarcoleptics.
[单项选择]According to the passage, scientists have decided that sulfur aerosols from volcanic eruptions affect global temperatures to a greater extent than ash clouds because
A. (A) the greenhouse gas effect produced by human activities tends to have a much greater environmental effect than that of volcanic explosions
B. (B) clouds of sulfur-rich gases tend to achieve greater heights in the stratosphere than do ash clouds
C. (C) a particular explosion producing high sulfur and little ash had a greater environmental effect than the converse
D. (D) the burning of fossil fuels tends to exacerbate the effects of sulfurous aerosols, but not those of ash clouds
E. (E) global warming effects tend to minimize the impact of ash clouds, but not those of sulfurous aerosols
