题目内容

Trees are one of the oldest living things on earth .They play a very important role for human’s existence. Trees are important for life as they provide food and oxygen. The importance of tree continues to increase and more benefits of trees are being discovered as their role expands to satisfy the needs created by our modern lifestyles. The forests and trees that are planted by humans work together with us to make the world look better and more beautiful. __71____Some of them are as follows.

Trees can clean soil and control soil erosion. Poisonous chemicals and pollutants from various factories enter into the soil, thus causing soil pollution.___72____Soil erosion is a serious problem that causes degradation(退化)of soil and leads to floods. Trees and plant roots bind the soil and thus reduce soil erosion. Also they conserve rainwater and reduce sediment(沉积)deposits.

Trees produce oxygen . Trees play an important role in reducing the greenhouse gases. They consume carbon dioxide and produce oxygen.___73____A fully grown tree produces oxygen which is sufficient for10 people for a complete year. Also, they act as filters of the air that we breathe.

Trees are of commercial importance. Trees fulfill the need of fuel for cooking in many areas around the world. Trees also provide timber for furniture and hundreds of household items. Wood pulp is used for making paper in industries.____74____Some trees are even used to make medicines.

____75____They provide shelter and food for a number of animal species across the globe. Trees are especially important as they form green corridors connecting habitats with each other and with the countryside beyond.

A This lowers global warming.

B Trees have beautified our planet.

C Trees act as the habitat for wild animals.

D In face, trees play different roles in our environment.

E Without trees our planet cannot be considered a place for living.

F Also, trees produce a number of fruits and nuts which are sold at market.

G Trees have the ability to store them or change them into less harmful forms.

DGAFC

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完形填空

　　In 1980 a report was published about what the earth might be like 20 years from then. The report was the result of a three-year study.

　　According to the report, the 1 of the earth in the year 2000 is not a 2 one. The world will be more crowded because the 3 will continue to grow. The population 4 be as large as 6,300 million, almost 2,500 million more than that in 1975. 5 people would move into cities, especially cities in 6 countries. Cities like Cairo and Jakanta 7 would each have 15 million by then. Food production will increase, but not enough to feed all the people. Farmers will grow 90% more food than they did in 1975, but most of the increase would be in countries that 8 produce enough food for their people. 9 increase is grown in South Asia, Africa and European countries. Poor farming ways are 10 large areas of cropland, changing farms into 11 . More farmland is lost 12 cities become larger and houses are built. Air pollution will get worse as industrial countries 13 more coal and oil. Much of the world's 14 could disappear as more and more trees are cut down. Energy will continue to be a 15 problem. The experts hope their picture of the earth for the year 2000 may be 16 . Measures must be taken to change the situation that 17 today. By changing the situation, by settling the problems, the picture can be changed. There is 18 time for the nations of the world to work together on a plan of action. But they 19 that waiting too long to make decisions would greatly 20 the chances of success.

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When trees are cut down, there is nothing to hold the soil on the hillside.

A.
take place
B.
out of place
C.
in place
D.
in place of

Planting trees around poultry farms can improve air and water quality -- and relations with neighbors. Research has shown that just three rows of trees near poultry houses can reduce the release of dust and ammonia(氨). They can also reduce the strong smell of ammonia gas.

The trees take dust, ammonia and odors in their leaves. They also provide shade from the sun, so they reduce cooling costs in summer. And they act as a windbreak, so they reduce heating costs in winter. Trees can also improve water quality around farms by removing pollutions from soil and groundwater.

Several years ago, people were objecting to the odor of poultry farms on the Delmarva Peninsula in the eastern United States. Delmarva is where the states of Delaware, Maryland and Virginia come together. Two thousand farms there can each house an average of seventy-five thousand chickens.

Traditionally the farms used windows to provide fresh air in the chicken houses. Farmers rarely planted trees or tall crops around the buildings, so there would be no barrier to the airflow. But then farms began to use new ventilation systems. Instead of windows, the new systems used tunnel fans to circulate air. The fans directed airflow from the poultry houses toward the homes of neighbors.

Researchers began dealing with the problem in two thousand. They found that over a period of six years, planting three rows of trees reduced total dust and ammonia by more than half. And they found that smells were reduced by eighteen percent.

Farmers may think trees will take too long to grow and be effective. But some trees can grow quickly. At least one-third of the Delmarva farms have planted trees, technically known as vegetative environmental buffers. The idea offers a way to cut pollution, save money and energy, and make the neighbors happy.

The second paragraph mainly tells us ______.

A. planting trees as much as possible

B. the advantages of trees

C. how to reduce heating costs

D. why trees are received

The word “odor” in paragraph 3 means ______.

A. plant B. smell C. height D. water

The farms on the Delmarva Peninsula used to use ______ in chicken houses to provide fresh air.

A. trees B. tunnel fans C. windows D. poles

It can be learned from the last two paragraphs that ______.

A. three rows of trees are really good to the environment

B. researches began to realize the problem in 2000

C. most farmers show interest in planting trees

D. the trees growing quickly can be cut off in a few years

第二部分：语言知识及运用（满分25分）
第一节完形填空(共10小题；每小题1.5分，满分15分)
Trees are useful to man in three very important ways. They provide him with wood and other   __21__ ; they give him shade; they help to prevent drought(干旱)and __22__.
Unfortunately, in many parts of the world, man has not realized that the third of these services is the most important.
Two thousand years ago a rich and powerful country cut down its trees to build warships, with which to gain itself an empire. It gained the empire, but,__23__its trees, its soil became hard and poor. When the empire fell to__24__,the home country found itself faced by floods and starvation.
Even where a government realizes the importance of a plentiful supply of trees, it is difficult for__25__to persuade the villager to see this. The villager wants wood to cook his food with ; and he can earn money by making charcoal or selling wood to the townsman. He is usually too lazy or too careless to plant and look after new trees. So, unless the government has a good system of control, or can__26__the people, the forests will slowly disappear.
This does not only mean that the villagers’ sons and grandsons have__27__trees. The results are even more serious; for where there are trees, their roots break the soil up—allowing the rain to sink in—and also bind(结合)the soil, thus preventing its__28__washed away easily, but where there are no trees ,the rain falls on hard ground and carrying__29__with it the rich top soil, in which crops__30__so well. With all the topsoil gone, nothing remains but worthless desert.
21．A. uses                  B. products                   C. production                D. result
22．A. floods           B. soil                         C. air                           D .sunlight
23．A. with                 B. by                           C. on                           D. without
24．A. break        B. unite                        C. bits                          D. pieces
25．A. it                  B. them                        C. he                            D. they
26．A. ask                   B. educate                    C. want                        D. remove
27．A. a few            B. fewer                       C. a little                      D. little
28．A. been             B. being                       C. is                             D. was
29．A. away            B. off                           C. with                         D. by
30．A. come            B. grow                        C. get                           D. Turn

In the decade（十年）of the 1970s, the United Nations organized several important meetings on the human environment to study a very serious problem．We humans are destroying the world around us．We must learn to protect them, or life will be very bad for our children and grandchildren．
There are several major aspects to this problem．
Population
Most problems of the environment come from population growth．In 1700 there were 635 million people in the world; in 1900 there were 1．6 billion; in 1950, 2．5 billion; and in 1980, 4．4 billion．In the year 2010 there will be 7．3 billion．More people need more water, more food, more wood, and more petroleum．
Distribution
Scientists say there is enough water in the world for everyone, but some countries have a lot of water and some have only a little．Some areas get all rain during one season．The rest of the year is dry．
Petroleum
We are using up the world’s petroleum．We use it in our cars and to heat our buildings in winter．Farmers use petrochemicals to make the soil rich．They use them to kill insects on those plants．These chemicals go into rivers and lakes and kill the fish there．Thousands of people also die from these chemicals every year．Chemicals also go into the air and pollute it．Winds carry this polluted air to other countries and other countries．
Poverty
Poor farmers use the same land over and over．The land needs a rest so it will be better next year．However, the farmer must have food every year．Poor people cut down trees for firewood．In some areas when the trees are gone, the land becomes desert．However, people need wood to cook their food now．Poor people cannot save the environment for the future．
We now have the information and the ability to solve these huge problems．However, this is not a problem for one country or one area of the world．It is a problem for all humans．The people and the nation of the world must work together to protect the world’s resources．No one controls the future, but we all help make it．
【小题1】According to the passage, our world is being destroyed mainly because ______．

A．pollution is getting worse and worse

B．population are increasing greatly

C．we humans are using up all of our natural resources

D．distribution is not reasonable．

【小题2】Good distribution means ________．

A．having things in the right place at the right time．

B．cutting down forests and selling them to other countries．

C．building water systems to carry water to farms．

D．conserving our natural resources

【小题3】The best title of the passage should be ________

A．The World Being Destroyed

B．A Serious Problem We Should Pay Attention to

C．Aspects That Destroyed Our World

D．Conserving the World’s Natural Resources

When trees are cut down, there is nothing to hold the soil on the hillside.

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