填空题
As concerns over man's impact on the global
environment increase, many interesting innovations are being considered. For
example, "green roofs" - plant-filled roof top gardens - are one substantial way
to confront the country's ecological problems, and there seems to be very little
in the way of a downside. For one thing, a green roof acts as a sponge for
rainwater, absorbing the majority of water from a typical rainstorm. Only three
to five inches of soil for a green roof is sufficient for this to occur, which
keeps the weight of the roof to a minimum. Because the plantings on the roof
absorb the rainwater, drainage and sewage systems have a decreased volume of
water pumping through them, keeping these systems from becoming over-stressed.
And while, the soil and plants are absorbing rainwater, they are also taking in
pollutants for their own nourishment by storing carbon and then emitting
necessary oxygen back into the atmosphere.
单选题
The second and third sentences are characterized, respectively, by
A. warning and justification
B. generalization and specification
C. invocation and definition
D. authority and reverence
E. confession and resolution
【正确答案】
B
【答案解析】The passage begins with an assertion that green roofs are a viable solution to the country's ecological problems. It then continues with specific ways by which green roofs would help.
单选题
The author's main point in the passage is that
A. green roofs are expensive to install and maintain
B. green roofs are both innovative and eco-friendly
C. global warming concerns have led to many new inventions
D. plant-filled roof gardens emit oxygen into the atmosphere
E. green roofs are the definitive cure for global warming
【正确答案】
B
【答案解析】According to the passage, green roofs are an example of an interesting innovation that will help with our ecological problems. Therefore, choice B is the best answer. The remaining choices are either too specific or too broad.
单选题
The author references the absorption capabilities of green roofs
primarily in order to illustrate
A. a preoccupation with style over design practicality
B. the inefficiencies of installing plantings to a building's roof
C. how green roofs lead to more efficient and less-stressed home
systems
D. the increased public interest in environmental friendliness in the
construction industry
E. how global warming has accelerated society's interest in environmentally
friendly structures
【正确答案】
C
【答案解析】The passage focuses on specific examples of how the green roofs would work. The other answer choices are outside the scope of the passage.