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The planet is getting greener, and we are responsible. Carbon dioxide generated by human activities is promoting photosynthesis (光合作用) and causing a beneficial greening of the Earth’s surface.
For the first time, researchers claim to have shown that the increase in plant cover is due to this “CO2 fertilisation (肥沃化) effect” rather than other causes. However, it remains unclear whether the effect can reduce any negative effects of global warming, such as the spread of deserts.
To home in on the effect of CO2, Randall Donohue of Australia’s national research institute, the CSIRO in Canberra, monitored vegetation (植被) at the edges of deserts in Australia, southern Africa, the US Southwest, North Africa, the Middle East and central Asia. These are regions where there is plenty of warmth and sunlight, but only just enough rainfall for vegetation to grow, so any change in plant cover must be the result of a change in rainfall patterns or CO2 levels, or both.
If CO2 levels were constant, then the amount of vegetation per unit of rainfall ought to be constant, too. However, the team found that this figure rose by 11 per cent in these areas between 1982 and 2010, mirroring the rise in CO2 emissions (排放). Donohue says this lends strong support to the idea that CO2 fertilization drove the greening.
The extra plant growth could have knock-on effects on climate, Donohue says, by increasing rainfall, affecting river flows and changing the likelihood of wildfires. It will also absorb more CO2 from the air, potentially damping down (抑制) global warming but also limiting the CO2 fertilization effect itself.
Donohue cannot yet say to what extent CO2 fertilisation will affect vegetation in the coming decades. But if it proves to be significant, the future may be much greener.
According to the author, the increase in plant cover _____.

A.will speed up global warming
B.results from human activities
C.will stop the spread of deserts
D.promotes the CO2 fertilization effect

What does the underlined phrase “To home in on” in Para 3 probably mean?

A.To hold back. B.To cut down.
C.To improve. D.To observe.

The amount of vegetation in those monitored areas rose with _____.

A.the rise in CO2 emissions B.annual rainfall
C.the temperatures around D.the amount of sunlight

What’s the best title of the text?

A.More rainfall, less CO2 emission
B.How to deal with carbon emissions
C.Positive effects of global warming
D.CO2 emission making Earth greener
科目 英语   题型 阅读理解   难度 中等
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The physicians in a hospital form the center of medical staff. But they could not provide effective medical care to their patients without the help of numerous other medical employees. From the viewpoint of the patients, the nursing staff is particularly important. Nurses are usually in close contact with patients as long as they are in the hospital.
A nurse does not study for as many years as a doctor. however, each must be equally dedicated. Caring for sick persons requires a great deal of patience and concern. Most nurses work long days, and they often must work at odd hours or during the night.
Under the supervision (监管) of the head nurse, the nursing staff must provide nursing services on a 24-hour basis and attend to patients’ needs. This responsibility continues around the clock, and so nurses must work in shifts. A shift is a period of duty, usually eight in length. The nurses on the ward rotate their shifts. Some take turns working night duty; others work odd shifts.
A nurse must always be alert. She can never afford to be careless. This is true in all nursing situation, but it is especially true in the intensive care unit. Patients under intensive care are critically ill, and they must be monitored at all times. The nurses who do intensive care duty have one of the most demanding jobs in the hospital.
Serving as a nurse can be a very rewarding job. But it is not an easy one. Not every person is suited to become a nurse. Only very dedicated people have chosen nursing as a profession.
The nursing staff ________.

A.are central to the medical staff
B.play an important role in caring for patients
C.can work effectively without physicians
D.are always in close contact with the patients

Why don’t nurses study for as many years as doctors?

A.They don’t treat patients for illness and injury.
B.Most nurses work long days.
C.Caring for sick patients requires patience and concern.
D.They are not dedicated.

Nurses work in shifts because ________.

A.they are careless.
B.nursing services must be provided continuously.
C.they work at night from time to time.
D.a shift is usually eight hours long.

What kind of person is suited to become a nurse?

A.A very careful person. B.An able person.
C.A very dedicated person. D.A specially trained person.

The Neutrality of American in the Early World War II
The establishment of the Third Reich influenced events in American history by starting a chain of events which culminated in war between Germany and the United States. The compete destruction of democracy, the persecution of Jews, the war on religion, the cruelty and barbarism of the Nazis, and especially the plans of Germany and her allies, Italy and Japan, for world conquest caused great indignation in this country and brought on fear of another world war. While speaking out against Hitler’s atrocities, the American people generally favored isolationist policies and neutrality. The Neutrality Acts of 1935 and 1936 prohibited trade with any belligerents or loans to them. In 1937 the President was empowered to declare an arms embargo in wars between nations at his discretion.
American opinion began to change somewhat after President Roosevelt’s “quarantine the aggressor” speech at Chicago (1937) in which he severely criticized Hitler’s policies. Germany’s seizure of Austria and the Munich Pact for the partition of Czechoslovakia (1938) also aroused the American people. The conquest of Czechoslovakia in March, 1939 was another rude awakening to the menace of the Third Reich. In August, 1939 came the shock of the Nazi-soviet Pact and in September the attack on Poland and the outbreak of European war. The United States attempted to maintain neutrality in spite of sympathy for the democracies arrayed against the Third Reich. The Neutrality Act of 1939 repealed the arms embargo and permitted “cash and carry” exports of arms to belligerent nations. A strong national defense program was begun. A draft act was passed (1940) to strengthen the military services. A Lend Act (1941) authorized the President to sell, exchange, or lend materials to any country deemed necessary by him for the defense of the United States. Help was given to Britain by exchanging certain overage destroyers for the right to establish American bases in British territory in the Western Hemisphere. In August, 1940 President Roosevelt and Prime Minister Churchill met and issued the Atlantic Charter which proclaimed the kind of a world which should be established after the war. In December, 1941, Japan launched the unprovoked attack on the United States at Pearl Harbor. Immediately thereafter, Germany declared war on the United States.
One item occurring before 1937 that the author does not mention in his list of actions that alienated the American public was
A the burning of the Reichstag. B German plans for conquest.
C Nazi barbarism. D the persecution of religious groups.
The Lend-Lease Act was designed to
A help the British.
B strengthen the national defense of the United States.
C promote the Atlantic Charter.
D avenge Pearl Harbor.
American Policy during the years 1935-1936 may be described as being
A watchful. B isolationist. C peaceful. D indifferent.
The Neutrality Act of 1939
A permitted the selling of arms to belligerent nations.
B antagonized Japan.
C permitted the British to trade only with the Allies.
D led to Lend-Lease Act.
We entered the war against Germany
A because Germany declared war.
B because Japan was an ally of Germany.
C after Germany had signed the Nazi-soviet Pact.
D after peaceful efforts had failed.

We Should All Grow Fat and Be Happy
Here’s a familiar version of the boy-meets-girl situation. A young man has at last plucked up courage to invite a dazzling young lady out to dinner. She has accepted his invitation and he is overjoyed. He is determined to take her to the best restaurant in town, even if it means that he will have to live on memories and hopes during the month to come. When they get to the restaurant, he discovers that this ethereal creature is on a diet. She mustn’t eat this and she mustn’t that. Oh, but of course, she doesn’t want to spoil his enjoyment. Let him by all means eat as much fattening food as he wants: it’s the surest way to an early grave. They spend a truly memorable evening together and never see each other again.
What a miserable lot dieters are! You can always recognize them from the sour expression on their faces. They spend most of their time turning their noses up at food. They are forever consulting calorie charts; gazing at themselves in mirrors; and leaping on to weighing-machines in the bathroom. They spend a lifetime fighting a losing battle against spreading hips, protruding tummies and double chins. Some wage all-out war on FAT. Mere dieting is not enough. They exhaust themselves doing exercises, sweating in sauna baths, being pummeled and massaged by weird machines. The really wealthy diet-mongers pay vast sums for ‘health cures’. For two weeks they can enter a nature clinic and be starved to death for a hundred guineas a week. Don’t think it’s only the middle-aged who go in for these fads either. Many of these bright young things you see are suffering from chronic malnutrition: they are living on nothing but air, water and the goodwill of God.
Dieters undertake to starve themselves of their own free will; so why are they so miserable? Well, for one thing, they’re always hungry. You can’t be hungry and happy at the same time. All the horrible concoctions they eat instead of food leave them permanently dissatisfied. Wonderfood(奇妙的事物) is a complete food, the advertisement says. ‘Just dissolve a teaspoonful in water…’. A complete food it may be, but not quite as complete as a juicy steak. And, of course, they’re always miserable because they feel so guilty. Hunger just proves too much for them and in the end they lash out and devour five huge guilt-inducing cream cakes at a sitting. And who can blame them? At least three times a day they are exposed to temptation. What utter torture it is always watching others tucking into piles of mouth-watering food while you munch a water biscuit and sip unsweetened lemon juice!
What’s all this self-inflicted torture for? Saintly people deprive themselves of food to attain a state of grace. Unsaintly(saintly<圣洁的>的反义词) people do so to attain a state of misery. It will be a great day when all the dieters in the world abandon their slimming courses; when they hold out their plates and demand second helpings!
The best title for this passage is
A On Fat.
B We Should All Grow Fat and Be Happy.
C Many Diseases Are Connected with Fat.
D Diet Deprives People of Normal Life.
Why do they never see each other again?
A Because it is a memorable evening.
B Because she lets him eat as much fattening food as he wants.
C Because she does not eat this and drink that.
D Because eating fattening food is the surest way to an early grave.
Which of the following ways is NOT mentioned for diet?
A Doing exercises. B Not eating sugar. C Not eating fat. D Taking sauna baths.
What is the author’s attitude toward diet?
A Persuasive. B Critical. C Indifferent. D Adversative.

Antinuclear Demonstration
Police fired tear gas and arrested more than 5,000 passively resisting protestors Friday in an attempt to break up the largest antinuclear demonstration ever staged in the United States. More than 135,000 demonstrators confronted police on the construction site of a 1,000-megawatt nuclear power plant scheduled to provide power to most of southern New Hampshire. Organizers of the huge demonstration said, the protest was continuing despite the police actions. More demonstrators were arriving to keep up the pressure on state authorities to cancel the project. The demonstrator had charged that the project was unsafe in the densely populated area, would create thermal pollution in the bay, and had no acceptable means for disposing of its radioactive wasters. The demonstrations would go on until the jails and the courts were so overloaded that the state judicial system would collapse.
Governor Stanforth Thumper insisted that there would be no reconsideration of the power project and no delay in its construction set for completion in three years. “This project will begin on time and the people of this state will begin to receive its benefits on schedule. Those who break the law in misguided attempts to sabotage the project will be dealt with according to the law,” he said. And police called in reinforcements from all over the state to handle the disturbances.
The protests began before dawn Friday when several thousand demonstrators broke through police lines around the cordoned-off construction site. They carried placards that read “No Nukes is Good Nukes,” “Sun-power, Not Nuclear Power,” and “Stop Private Profits from Public Peril.” They defied police order to move from the area. Tear gas canisters fired by police failed to dislodge the protestors who had come prepared with their own gas masks or facecloths. Finally gas-masked and helmeted police charged into the crowd to drag off the demonstrators one by one. The protestors did not resist police, but refused to walk away under their own power. Those arrested would be charged with unlawful assembly, trespassing, and disturbing the peace.
What were the demonstrators protesting about?
A Private profits. B Nuclear Power Station.
C The project of nuclear power construction. D Public peril.
Who had gas-masks?
A Everybody. B A part of the protestors.
C Policemen. D Both B and C.
Which of the following was NOT mentioned as a reason for the demonstration?
A Public transportation. B Public peril.
C Pollution. D Disposal of wastes.
With whom were the jails and courts overloaded?
A With prisoners. B With arrested demonstrators.
C With criminals. D With protestors.
What is the attitude of Governor Stanforth Thumper toward the power project and the demonstration?
A stubborn. B insistent. C insolvable. D remissible.

Superconducting Materials
The stone age, The Iron Age. Entire epochs have been named for materials. So what to call the decades ahead? The choice will be tough. Welcome to the age of superstuff(超级材料). Material science -- once the least sexy technology – is bursting with new, practical discoveries led by superconducting ceramics that may revolutionize electronics. But superconductors are just part of the picture: from house and cars to cook pots and artificial teeth, the world will someday be made of different stuff. Exotic plastics, glass and ceramics will shape the future just as surely as have genetic engineering and computer science.
The key to the new materials is researchers’ increasing ability to manipulate substances at the molecular level. Ceramics, for example, have long been limited by their brittleness. But by minimizing the microscopic imperfections that cause it, scientists are making far stronger ceramics that still retain such qualities as hardness and heat resistance. Ford Motor Co. now uses ceramic tools to cut steel. A firm called Kyocera has created a line of ceramic scissors and knives that stay sharp for years and never rust or corrode.
A similar transformation has overtaken plastics. High-strength polymers now form bridges, ice-skating rinks and helicopter rotors. And one new plastic that generates electricity when vibrated or pushed is used in electric guitars, touch sensors for robot hands and karate jackets that automatically record each punch and chop. Even plastic litter, which once threatened to permanently blot the landscape, has proved amenable to molecular tinkering. Several manufacturers now make biodegradable forms; some plastic six-pack rings for example, gradually decompose when exposed to sunlight. Researchers are developing ways to make plastics as recyclable as metal or glass. Besides, composites – plastic reinforced with fibers of graphite or other compounds – made the round-the-world flight of the voyager possible and have even been proved in combat: a helmet saved an infantryman’s life by deflecting two bullets in the Grenada invasion.
Some advanced materials are old standard with a new twist. The newest fiberoptic(光学纤维的) cable that carry telephone calls cross-country are made of glass so transparent that a piece of 100 miles thick is clearer than a standard window pane.
But new materials have no impact until they are made into products. And that transition could prove difficult, for switching requires lengthy research and investment. It can be said a firmer handle on how to move to commercialization will determine the success or failure of a country in the near future.
How many new materials are mentioned in this passage?
A Two B Three C Four D Five
Why does the author mention genetic engineering and computer science?
A To compare them with the new materials.
B To show the significance of the new materials on the future world.
C To compare the new materials to them.
D To explain his view point.
Why is transition difficult?
A Because transition requires money and time.
B Because many manufacturers are unwilling to change their equipment.
C Because research on new materials is very difficult.
D Because it takes 10 years.
Where lies success of a country in the New Age of superstuff?
A It lies in research. B It lies in investment.
C It lies in innovation. D It lies in application.

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