题目内容

Many plants and animals on the earth have ________, and some other species are endangered.

A.
died out
B.
died away
C.
died up
D.
died off

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　　For years scientists have been worried about the effects of air pollution on the earth’s natural conditions. Some believe the air inside many houses may be more dangerous than the air outside. It may be one hundred times worse.

　　Indoor air pollution can cause a person to feel tired, to suffer eye-pain, headache and other problems. Some pollutants（污染物） can cause breathing disorders, diseases of blood and even cancer, Most scientists agree that every modern house has some kind of indoor pollution. People began to notice the problem in the early 1970s. It is that when builders began making houses and offices they did not waste energy. To do this they built buildings that limited the flow of air between inside and outside. They also began using manmade building materials. These materials are now known to let out harmful gases. As the problem became more serious, scientists began searching for a way to deal with it. They discovered a natural pollution control system for building— green plants. Scientists do not really know how plants control air pollution. They believe that a plant’s leaves absorb or take in the pollutants. In exchange the plant lets out oxygen through its leaves and through its tiny organizations on its roots. Scientists suggest that all buildings should have one large plant or several small plants inside for every nine square metres of space. Studies of different plants show that each absorbs different chemicals. So the most effective way to clean the air is to use different kinds of plants. Having green plants inside your house can make it a prettier and more healthy place.

　　Generally speaking, indoor air pollution may be more harmful than the air outside because ________.

　　A. the man - made building materials let out dangerous gases inside houses

　　B. there may be more harmful gases outside houses

　　C. the flow of air indoors is limited

　　D. indoor air pollution can make a person seriously ill

　　The most effective way to clean the air is to use different kinds of plants because________.

　　A. they may let out more oxygen which people need

　　B. they can absorb different kinds of the harmful indoor chemicals

　　C. they can take in all kinds of indoor pollutants

D. they can make your house prettier and more healthy

As China becomes increasingly urbanized (城市化), it has to find space for its urban and rural citizens as both groups become increasingly integrated. Experts suggest a possible model way may be “re-inventing” a “garden city”.

China’s mega-cities are bursting at the borders and the country is now undergoing the quickest and biggest urbanization in the history of mankind. It is estimated that by 2025, China will have 400 million more people living in its cities, raising its urban population to 900 million. Besides, new satellite towns are mushrooming on the urban fringes while city ring roads are rippling outwards into the countryside at amazing speed. Satellite maps collected by Professor Joshua Bolchover at the University of Hong Kong bring the problem sharply into focus. They track the changing rural-urban framework in the past 30 years, and suggest that cities are cruelly destroying surrounding rural land and rapidly reducing the amount of arable (可耕种的) land, which gives way to new residential blocks, new industrial zones, new financial centers and the other inevitable signs and signatures of economic growth.

This, however, is not sustainable growth pattern, especially when China has the world’s largest population to feed. So concerned urban planners are starting to note the social and physical effects of diaspora (大移居) when replaced rural communities are forced into the cities.

On the other hand, a trend of thought is gradually taking shape and this is the concept of the “garden city”, a combination of country and city that is being proposed by architects and city planners. Hua Li, from Tao Architects, is among the many professionals with such a voice. His argument is supported by a long-term study on this subject. As Hua says, the answer is to preserve patches of productive farmland within urban boundaries. Less transportation means we have fresh agricultural products at lower costs and less carbon emission in the city. And urban farmland can also be showcased for agricultural tourism and education.

The concept is already practiced at the grassroot level. Agriculture has gone into the air, up to roof and balcony in some communities in the cities. It’s common to see organic “hanging garden” on the roof of some traditional courtyard home. According to some people, the rooftop project translate to tangible (=" practical)" benefits, such as safe, nutritious vegetables, a cooler home in summer. Some say thanks to the tomatoes they plant that are natural insect killers, there’re fewer mosquitoes. Apart from these, it also contributes to better bonding with neighbors. Zhang, a doctor in Beijing, began creating his hanging garden five years ago. Since his garden became home to 30 kinds of vegetables and fruit --- all enough to feed his family, neighbors have enjoyed dropping by for a relaxing chat or just to see how well the lovely vegetables and fruit are doing.

Although people like Zhang are still rare and the greening of roof space with vegetables and fruit takes skill and energy, with more positive media exposure and advanced technology there is the prospect that garden city will become common practice in the near future. By then, cities will no longer look so gray when seen from the satellites.

1.Some experts suggest re-inventing a “garden city” because ______.

A．it is the only model way to save the cities

B．it helps stop destroying the rural areas

C．increasing urbanization takes place in China

D．China has the largest population to feed

2.What is the purpose of paragraph 2?

A．To show the experts’ concern about the increase of population.

B．To persuade people into supporting economic growth in cities.

C．To explain the reasons for the change of rural-urban framework.

D．To inform the readers of the consequences of quick urbanization.

3.In Hua Li’s opinion, a combination of country and city will ______.

A．benefit the environment and lower living costs

B．become a project that needs a long-term study

C．lead to more rural communities being replaced

D．attract more farmers to take tours in cities

4.Zhang is mentioned (Paragraph 5) to show that ______.

A．he achieves his dream to own a hanging garden

B．hanging gardens are becoming more popular

C．the garden contributes to a better neighborhood

D．he is a pioneer to practise the gardening concept

5.As for the concept of the “garden city”, the writer feels ______.

A．desperate B．hopeful C．disappointed D．concerned

The deadly earthquake and tsunami (海啸) that struck Japan on March 11 damaged two nuclear power stations. Officials are now working to prevent dangerous radiation from poisoning the air in the area surrounding the Fukushima Daiichi plant. The Japanese government has ordered people living within 12 and a half miles of the plant to evacuate, and asked those living 12 and a half to 20 miles away to stay indoors.

Nuclear power plants create energy using a chemical reaction that produces large amounts of heat. Reactors(反应堆)in Japan have many long, thin rods, called fuel rods(棒), which must be kept cool.

If the reactor’s fuel rods aren’t cooled, the reaction can burn out of control. That’s what happened at the two Japanese plants after the quake caused a power failure and the cooling systems malfunctioned(发生故障). This overheating could cause radiation to escape and sicken many people.

Japan’s 54 nuclear reactors are built to withstand the many small or moderate earthquakes the country faces each year. But Friday’s earthquake was one of the most severe earthquakes ever recorded.

People exposed to unsafe levels of radiation have a higher than normal risk of getting cancer. The Japanese government has been distributing potassium iodide(碘化钾)pills to people in the surrounding areas to protect those who may have come in contact with radiation from the power plant. The pills flood the body with healthy potassium iodide. The potassium iodide works to crowd out “bad” iodine in the body that may have been poisoned by radiation.

On Tuesday morning, 750 workers left the Fukushima Daiichi plant. However, 50 workers stayed behind to use sweater to cool the fuel rods. These dedicated employees are risking their own lives to save many others.

On Thursday, officials used helicopters, fire trucks, and water cannons to spray water on the reactors to cool the fuel rods. But it’s not clear whether these efforts were successful. Officials are now working on a power line to restore electricity to the plant. They hope this will help restart the plant’s cooling system and stop the fuel rods from leaking radiation.

1.The underlined word “evacuate” in Paragraph 1 probably means .

A．help

B．rest

C．stop

D．leave

2.What can we learn from the text?

A．The local people are scared and ready to run away.

B．The earthquake led to many deaths and caused damage to roads.

C．The Japanese government has found a kind of pill that can treat cancer.

D．The two stations were damaged because their cooling systems didn’t work.

3.In the last paragraph, the author mainly states .

A．lack of help

B．international aids

C．the government’s efforts

D．the result of the disaster

4.This text is most probably taken from .

A．a research paper

B．a newspaper report

C．a class presentation

D．a chemistry textbook

Plants are chemical factories. Many of the chemicals that they produce are useful to humans. Besides food, plants provide material for paper, buildings, medicines and many others. Scientists study the chemicals to treat certain types of cancer.

On the other hand, the fast growth of the human population is changing the earth quickly. Only by understanding how human activities affect our environment can we predict global climate changes. Scientific studies of these changes and their effect on natural ecosystems and crop production are of great importance to the future of our society.

Other environmental issues, such as pollution, also interest scientists. Many plant species are especially sensitive to certain pollutants. Scientists study the effects of different types of pollution on plants. They use their results to advise lawmakers to make laws for environmental protection and to save priceless natural areas.

By using plant tissue culture（植物细胞培养），scientists can grow plants from single cells. This has exciting possibilities in biotechnology, forestry and so on. For example, the American chestnut was once a widespread tree in the Eastern forests. Today it has nearly disappeared because of a disease-producing fungus that causes chestnut to die. The American chestnut recently has been grown in plant tissue culture.

The earth’s biological diversity or the kinds of living things are decreasing. As humans change the environment for their own purposes, plants and animals living in these areas become increasingly endangered．Scientists work to identify and understand new plant species, especially in such biologically rich areas as rain forests. Perhaps a plant undiscovered now will become an important food crop. There are probably many undiscovered plants that produce useful drugs to cure or treat human disease. Biological diversity also provides an important source of new genes to improve the plants we now use. As techniques of genetic engineering improve, so will our ability to improve our plants.

1．Which of the following is not true according to this passage?

A．All the chemicals we need are produced by plants.

B．If we can understand how human activities affect our environment, we can predict global climate changes.

C．Science plays an important role in improving the plants.

D．Scientists use their scientific study results to make laws for environmental protection and to save priceless natural areas.

2．We can know from the Paragraph2 and Paragraph3 that_______.

A．it is global climate changes that endanger plant

B．human activities influence plants greatly

C．pollution does little harm to many plants

D．scientific studies on plant species are important to stop pollution

3．The underlined sentence means___________.

A．plants can produce many chemicals needed in chemical factory

B．plants can be made into many products in factories

C．scientists can use plants to study many chemicals

D．scientists can offer people many necessary materials

4．The importance of biological diversity lies in that_____________________.

A．we can have new species to take the place of the endangered

B．it can populate the earth with as many plants as possible

C．it has many possible values to human being

D．people may use it to cure or treat human disease

5．The best title for the passage might be ____________.

A．Finding New Plant Species

B．Botany and Society

C．The Chemical Factories

D．New Genes to Improve the Plants

Imagine putting a seed in a freezer, waiting 30,000 years, and then taking the seed out and planting it. Do you think a flower would grow?
　 Amazingly, scientists have just managed to do something very similar. They found the fruit of an ancient plant that had been frozen underground in Siberia — a region covering central and eastern Russia — for about 31,800 years. Using pieces of the fruit, the scientists grew plants in a lab. The new blooms have delicate white petals. They are also the oldest flowering plants that researchers have ever revived from a deep freeze.
　 “This is like regenerating a dinosaur from tissues of an ancient egg,” said University of California, Los Angeles biologist Jane Shen-Miller.
　 The plant has a long history. Back when mammoths and woolly rhinoceroses walked the land, an Arctic ground squirrel buried seeds and fruits in an underground chamber near the Kolyma River in northeastern Siberia. The ground became permafrost, a layer of soil that stays frozen for a long time.
　 Recently, Russian scientists dug out the old squirrel hole and found the plant remains 38 meters below the surface. Back at the lab, the team fed nutrients to tissue from three of the fruits to grow shoots. Then the scientists transferred the shoots to pots filled with soil. The plants produced seeds that could be used to grow even more of them.
　 It’s important for scientists to know that plant tissues can still be revived after being frozen for a long time. That’s because many researchers are trying to preserve the seeds of modern plants by freezing them and then storing them in giant lockers at various spots around the globe. One such endeavor, an underground facility in Norway, is called the Svalbard Global Seed Vault. It stores hundreds of thousands of frozen seeds. If a plant ever goes extinct, scientists could bring it back by taking its seeds from the Svalbard or other storage lockers.
　 “No one knows how long they are able to live for, but freezing is basically the format for many plant conservation attempts nowadays.” Shen-Miller said. It’s a good thing that at least some plants are tough enough to survive the experience.

64. How did the fruit originally get underground?
　 A. It was placed there by an animal. 　

B. It was trapped there during the ice-age.
C. It was planted there by ancient farmers.　　

D. It was buried there after the earthquake.
65. Why are scientists interested in this discovery?
　 A. It helps them learn how plant life has changed in the past 30,000 years.
　 B. It can help guide future efforts to protect endangered plant-life.
　 C. It can provide directions for where to look for other ancient plants.
　 D. It proves that all plant life can survive for thousands of years when frozen.
66. The underlined word “they” in the final paragraph refers to _______.
　 A. plants　 B. seeds　C. scientists 　D. storage lockers
67. The purpose of the passage is to _______.
　 A. discuss a plant conservation effort　　　 B. introduce some ancient plants
　 C. outline some causes of global warming　 D. describe a scientific research project

Many plants and animals on the earth have ________, and some other species are endangered.

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