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Lisa told the boss that she refuse to a____________ the meeting and that she would tell the reason tomorrow.
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If better use is of your spare time, you’ll make great progress in it.
A. spent B. made C. taken D. thought
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We produce 500 billion of plastic bags in a year worldwide and they are thrown away polluting oceans, killing wildlife and getting dumped in landfills where they take up to 1,000 years to decompose. Researchers have been unsuccessfully looking for a solution.
The 16-year-old Canadian high school student, Daniel Burd, from Waterloo Collegiate Institute, has-discovered a way to make plastic bags degrade(降解) in as few as 3 months, a finding that won him first prize at the Canada Wide Science Fair, a $10,000 prize, a $20,000 scholarship, and a chance to revolutionize a major environmental issue.
Burd’s strategy was simple: Since plastic does eventually degrade, it must be eaten by microorganisms (微生物). If those microorganisms could be identified, we could put them to work eating the plastic much faster than under normal conditions.
With this goal in mind, he grounded plastic bags into a powder and concocted(調(diào)制) a solution of household chemicals, yeast(酵母) and tap water to encourage microbes growth. Then he added the plastic powder and let the microbes work their magic for 3 months. Finally, he tested the resulting bacterial culture on plastic bags, exposing one plastic sample to dead bacteria as a control. Sure enough, the plastic exposed to the live bacteria was 17% lighter than the control after six weeks.
The inputs are cheap, maintaining the required temperature takes little energy because microbes produce heat as they work, and the only outputs are water and tiny levels of carbon dioxide.
“Almost every week I have to do chores and when I open the closet door, I have piles of plastic bags falling on top of me. One day, I got tired of it and I wanted to know what other people are doing with these plastic bags. The answer: not much. So I decided to do something myself.” Said Daniel Burd.
1. Daniel Burd won first prize at the Canada Wide Science Fair because .
A. he found a new kind of microorganism
B. he contributed much to environmental protection
C. he found a way to degrade plastics in shorter time
D. he could encourage microbe growth in an easier way
2. Daniel Burd exposed one plastic sample to dead bacteria to .
A. make the live bacteria work better B. test how effective his method was
C. know which bacteria worked faster D. control the temperature in the process
3. Maintaining the required temperature takes little energy because .
A. plastics can get hot easily B. microbes can produce heat themselves
C. much carbon dioxide is produced D. the temperature can be controlled
4. Daniel Burd got his idea from .
A. his school textbook B. the failure of researchers
C. his everyday work D. the practice of other people
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____ winter ___ on, it’s time to buy warm clothes.
A.With; to come B.With; coming
C.As; coming D.As; to come
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Australian scientists are trying to give kangaroo-style stomachs to cattle and sheep in order to cut the greenhouse gases they send out, which is thought to be responsible for global warming.
Thanks to special bacteria in their stomachs, kangaroo flatulence(腸胃氣脹)contains no methane(甲烷)and scientists want to transfer that bacteria to cattle and sheep who produce large quantities of the harmful gas.
While the usual image of greenhouse gas pollution is a billowing smokestack(煙囪)pushing out carbon dioxide, farm animals’ passing wind contribute a surprisingly high percentage of total emissions(排放物)in some countries.
“Fourteen percent of emissions from all sources in Australia is from enteric methane from cattle and sheep,” said Athol Klieve, a senior research scientist with the Queensland state government.
“And if you look at another country such as New Zealand, which has got a much higher agricultural base, they’re actually up around 50 percent,” he said.
Researchers say the bacteria also makes the digestive process much more efficient and could potentially save millions of dollars in feed costs for farmers.
But it will take researchers at least three years to isolate(分離)the bacteria, before they can even start to develop a way of transferring it to cattle and sheep.
Another group of scientists, meanwhile, has suggested Australians should farm fewer cattle and sheep and just eat more kangaroos. And about 20 percent of health-conscious Australians are believed to eat the national symbol already.
“It’s low in fat, it’s got high protein levels and it’s very clean in the sense that basically it’s the free-range(放養(yǎng)的)animal,” said Peter Ampt of the University of New South Wales’s institute of environmental studies.
1. Scientists intend to put bacteria into cattle and sheep ________.
A. to prevent them from sending out harmful gases
B. to help Australian farmers to earn more money
C. so that they can protect Australian ecosystem
D. so that they can make full use of special bacteria
2. Athol Klieve seems to believe that ________.
A. cattle and sheep produce more carbon dioxide
B. less cattle and sheep are raised in New Zealand
C. farm animals are to blame for greenhouse gases
D. New Zealand has the most animals in the world
3. The main idea of the text is to ________.
A. discuss a better way to protect the each B. warn farmers of the danger of animal waste
C. illustrate the possible solutions to pollution D. present a recent study on global warming
4. The advantages Peter Ampt lists about kangaroos don’t include ________.
A. it is rich in protein B. is low in fat
C. it is cheaper than beef D. it is cleaner than sheep
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A new cinema ______ here. They hope to finish it next month.
A. will be built B. is built C. has been built D. is being built
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Only having r ______ vegetables, fruit and water for a dinner could not offer enough energy.
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–Are you hungry?
--Yes. I ________.
A. have starved B. will be starved to death C. I am starving D. starve to death.
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The young man, when questioned why he the law, just looked at the policeman and said nothing.
A. had broken B. broke C. breaks D. was breaking
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We are at your service. Don’t to turn to us if you have any further problems.
A. beg B. hesitate C. desire D. seek
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