单项选择题"Copy the ways of nature", we were told. Yes, copy Nature—for everything comes directly or indirectly from natural things. Often we have to put our knowledge to work, treating Nature’s materials so as to make them serve our purposes better. We could, certainly, take the skin from a dead animal and at once make a pair of shoes with it; but they wouldn’t be very good shoes. For our purpose it is better first to treat the skin with chemicals that turn it into leather.
Why is it necessary for us to treat Nature’s material
Why is it necessary for us to treat Nature’s material
A. An animal’s skin is not really useful to us.
B. Our purposes can be better served.
C. Natural materials are limited.
D. It is difficult to copy natur
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1.单项选择题The other, more publicly acceptable form of geo-engineering would focus on removing carbon from the atmosphere and storing it underground. Known as carbon capture and storage (CCS), this idea is behind today’s experimental clean-power plants, which are attracting lots of research and funding. But clean, coal plants will only reduce future emissions, which does not address the root of the problem. Among all the uncertainties that still surround climate change, one thing has become clear: the scary durability of carbon, which will hang in the air for a thousand years, continuing to warm the planet no matter how drastically future emissions are cut. So there is a growing urgency behind the geo-engineer’s dream: to change the climate by artificial means, either sucking the existing carbon out of the air or cooling the air with solar reflectors.
Why is carbon so scary according to the passage
Why is carbon so scary according to the passage
A. It will contihue to warm the globe for many years.
B. It cannot be easily captured and stored.
C. Its emission will increase in the coming years.
D. It cannot be reflected back into the spac
3.单项选择题Cigarettes and mental illness have always tend to go together. An estimated 1.25 billionpeople smoke worldwide. Yet people who are depressed or anxious are twice as likely to smoke, and up to 88 per cent of those with psychotic disorders such as schizophrenia are smokers. A recent American survey concluded that around half of all cigarettes bum in the fingers of those with mental illness.
Recent American survey showed that.
Recent American survey showed that.
A. there are 1.25 billion smokers worldwide.
B. 88% of people with psychotic disorders are smokers.
C. about 625 million smokers have mental problems.
D. 2.5 billion people have mental problems worldwid
5.单项选择题A municipal management plan for storm-water runoff is mandated by the Clean Water Act. Early this year, Urban Stormwater Management in the United States, a report commissioned by the Environmental Protection Agency (EPA), recommended a number of ways to manage runoff, including using structural devices, like the kind AbTech produces. Rink is hoping that his merchandise appeals to budget-strapped municipalities. "Compared with building new storm-water treatment plants or upgrading already existing facilities to handle runoff pollution, which would cost in the millions of dollars, our products are very affordable," he says. The federal stimulus bill could make them even more so.
AbTech products are
AbTech products are
A. structural devices.
B. the best solution to run off.
C. appealing to budget-strapped municipalities.
D. costly.
6.单项选择题Lunge cancer, hypertension, heart disease, birth defects—we are all too familiar with the danger of smoking. But add to that list a frightening new concern. Mental illness. According to some controversial new findings, if smoking does not kill you, it may, quite literally, drive you to despair.
The tobacco industry openly pushes its product as something to lift your mood and soothe anxiety. But the short-term feel-good effect may mask the truth :that smoking may women or even trigger anxiety disorders, panic attacks and depression ,perhaps even schizophrenia (精神分裂症)
What is the main idea of the two paragraphs
The tobacco industry openly pushes its product as something to lift your mood and soothe anxiety. But the short-term feel-good effect may mask the truth :that smoking may women or even trigger anxiety disorders, panic attacks and depression ,perhaps even schizophrenia (精神分裂症)
What is the main idea of the two paragraphs
A. Smoking causes great dangers to the body.
B. Smoking is a good way to soothe anxiety.
C. Smoking probably leads to mental illness.
D. Smoking does not kill smokers.
7.单项选择题How sleep helps us consolidate memories is still largely a mystery. A recent study from the University of Lǔbeck, in Germany, offers one clue. Subjects were given a list of 46 word pairs to memorize, just before sleep. Then when they reached the deepest stages of sleep, electrical currents were sent through electrodes on their heads to induce very slow brain waves. Such slow waves were induced at random in the brains of one group of subjects, but not another.
The next morning, the slow-wave group had better recall of the words. Other types of memory were not improved, and inducing the slow waves later in the night did not have the same effect. Why and how the slow waves improved memory is not yet understood, but they are thought to alter the strengths of chemical connections, or synapses, between specific pairs of nerve cells in the brain. Memories are "stored" in these synapses: changing the strength of the synapses increases the strength of the memories they store.
Slow waves functioned in the subjects’ brains in the experiment when
The next morning, the slow-wave group had better recall of the words. Other types of memory were not improved, and inducing the slow waves later in the night did not have the same effect. Why and how the slow waves improved memory is not yet understood, but they are thought to alter the strengths of chemical connections, or synapses, between specific pairs of nerve cells in the brain. Memories are "stored" in these synapses: changing the strength of the synapses increases the strength of the memories they store.
Slow waves functioned in the subjects’ brains in the experiment when
A. they were given a list of words before sleep.
B. they reached the deepest stages of sleep.
C. they were connected to electrical currents.
D. they were asked to recall the words the next mornin
8.单项选择题This is not only an American problem, but a global one. The energy demand is driven by population growth especially in developing countries, in places that have emerging middle classes. Their focus is now on growth and on providing lifestyle and energy to their population. It’s not environment. But they’ll have to focus on it and do something about it.
Developing countries focus on all the following EXCEPT
Developing countries focus on all the following EXCEPT
A. economic growth.
B. providing lifestyles to people.
C. providing energy to people.
D. protecting the environment.
9.单项选择题The first generation of dot-corns burned through cash rapidly because they had to spend a lot of money building and running their businesses—marketing and advertising to get the word out, not to mention software, consultants, and programmers to run online systems and" analyze theresults. Thanks to Web 2.0, many of these costs have plummeted. Many of the basics are nowessentially free, which means a business built on the infrastructure laid down by the first two generations of Web companies can gain scale on a shoestring budget, all while giving away its products and services for free. Call it Web 2.5.
The first generation dot-coms spent a huge sum of money
The first generation dot-coms spent a huge sum of money
A. marketing and advertising their products.
B. training their employees.
C. hiring consults and programmers.
D. analyzing the data transmitted onto the we
10.单项选择题With regular exercise, the body builds up its levels of BDNF (brain-derived neurotrophic factor), and the brain’s nerve cells start to branch out, join together and communicate with each other in new ways. This is. the process that underlies learning: every change in the junctions between brain cells signifies a new fact or skill that’s been picked up and stowed away for future use. BDNF makes that process possible. Brains with more of it have a greater capacity for knowledge. On the other hand, says UCLA neuroscientist Fernando Gámez-Pinilla, a brain that’s low on BDNF shuts itself off to new information,
What will happen if a person has a brain that’s low on BDNF
What will happen if a person has a brain that’s low on BDNF
A. He will be able to learn many new skills.
B. He will forget all the information stored in his brain.
C. He will be able to learn things quickly.
D. He will not pick up new information quickly.
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