Trees should only be pruned （修剪, 整枝) when there is a good and clear reason for doing s

第1题

Trees should only be pruned （修剪) when there is a good reason for doing so. Many gardener

Trees should only be pruned (修剪) when there is a good reason for doing so. Many gardeners believe that more damage results from doing it unnecessarily than from leaving the tree to grow in its own way.

First, pruning may be done to make sure that trees have a desired shape. The object may be to get a tree of the right height, and to help the growth of small side branches which will thicken its appearance or give it a special shape. Secondly, pruning may be done to make the tree healthier. You may cut out diseased or dead wood, or branches that are rubbing against each other and thus causing wounds. A tree may grow healthier by removing the branches that are locking up the centre and so preventing the free movement of air.

One result of pruning is that an open wound is left on the tree and this provides an easy entry (进入) for diseases, but it is a wound that will heal. Often there is a race between the healing and the disease as to whether the tree will live or die. Pruning is usually clone in winter, for then you can see the shape of the tree clearly without the interference from the leaves.

According to the article, which of the following statement is NOT true？

A．Pruning is necessary when there are unwanted branches.

B．Damage is done to a tree if it is left to grow in its own way.

C．Diseased or dead branches should be cut away if they are found to rub against each other.

D．Growing side branches often prevent air from moving freely.

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第2题

Are you superstitious？ No, of course not. Do you believe in magic （魔法), and luck charms

Are you superstitious？ No, of course not. Do you believe in magic (魔法), and luck charms (护身符), and elves or gremlins (小精灵) ？ Certainly not, but if I should greet you with the usual How's business？" You'll answer "Oh, just so-so" although your business is profiting greatly. When you are successful in some venture you might say you were just lucky. And yet, you know it was probably due to your a bility and hard work. Why？ Sometimes you knock on wood because wood was once a tree and there is a primitive belief that protective gods inhabit trees and knocking on wood attracts their attention so they may be credited with your successes.

If I should sneeze, only the strongest of you could refrain(克制而不) from saying "God bless you". Why bless this unsanitary (不讲究卫生的) habit？ Our ancestors believed that a sneeze opened the body to invasion by devils, and invoking (召唤) the name of God made the devils get out in a hurry. You may not realize it, but you express this same "devil invasion" when you say, "Whatever can have gotten into that child？" or "I wonder what possessed me to do that？"

Although they may no longer be believed, evidences of superstitions that have had their origins in the primitive fear of the unknown still exist in modern language and gestures.

The author ______.

A．believe that most people are superstitious

B．believe that very few people are superstitious

C．believes that there are still some evidences of superstitions in what we say and what we do

D．is superstitious

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第3题

Trees are useful to man in three important ways: they provide him with wood and other prod

ucts; they give him shade; and they help to prevent droughts and floods.

Unfortunately, in many parts of the world, man has not realized that the third of these services is the most important. (78)In his eagerness to make money from trees, he has cut them down in large numbers, only to find that without them he has lost the best friends he bad. And besides, be is usually too careless to plant and look after new trees. So the forests slowly disappear.

This does not only mean that man will have fewer trees. The results are even more serious: for where there are trees, their roots break up soil—allowing the rain to sink in—and also bind the soil, thus preventing it from being washed away easily; but where there are no trees, the rain falls on hard ground and flows away, causing floods and carrying away the rich top-soil. When all the top-soil is gone, nothing remains but worthless desert.

Two thousand years ago a rich and powerful country cut down its trees to build warships, with which to gain itself an empire. It set up the empire but, without its trees, its soil became poor and it grew weak. When the empire fell to pieces, the home country found itself faced with floods and starvation.

What is the most important service of trees to man according to the passage？

A．They help him make money.

B．They give. him wood and other products.

C．They help him prevent droughts and floods.

D．They give him shade.

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第4题

Do you want to know something about the history of weather？ Don't look at the sky. Don't l

ook for old weather reports. Looking at tree rings is more important. Correct weather reports date back only one century, but some trees can provide an exact record of the weather even further back. (53) It is natural that a tree would grow best in a climate with plenty of sunlight and rainfall. It is also expected that little sunlight or rainfall would limit the growth of a tree. The change from a favorable to an unfavorable climate can be determined by reading the pattern of rings in a tree trunk. (54)To find out the weather of ten years age, count the rings of a tree trunk from the outside to the inside. If the tenth ring is far from the other rings, then it is certain that plenty of sunny and rainy weather occurred. If the ring are close together, then the climate was bad for the tree. Studying tree rings is important not only for the history of weather, but also for the history of man. In a region of New Mexico you can find only sand-no tree and no people. However, many centuries ago a large population lived there. They left suddenly. Why？ A scientist studied patterns of dead tree rings which had grown there. He decided that the people had to leave because they had cut down all the trees. Trees were necessary to make fires and buildings. So, after the people destroyed the trees, they had to move. In this instance studying tree rings uncovered an exciting fact about the history of man.

It is understood that in a favorable climate______.

A．tree rings grow close together

B．tree rings grow far apart

C．trees in New Mexico will grow big and tall

D．people can cut down most of the trees in New Mexico

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第5题

Trees are useful to man 【B1】______ three very important ways: they provide him 【B2】______

wood and other produces; they help to check soil erosion and they help to 【B3】______ drought and floods.

【B4】______ , in many parts of the world, man has not realized that the 【B5】______ of these services is the most important. In his eagerness to draw quick profit from the trees, he has cut them down in large 【B6】______ , only to find that 【B7】______ them he has lost the best friend he had.

Two 【B8】______ years ago a rich and powerful country cut down its trees to build warships 【B9】______ to gain itself an empire. It gained the empire, but without its trees, its soil became hard and poor. When the empire 【B10】______ to pieces, the home country found itself faced by floods and starvation.

【B11】______ a government realizes the importance of a plentiful supply of trees, it is difficult for it to persuade the villager to see this ,the villager wants wood to cook his food 【B12】______ ; and he can earn money by making charcoal or selling wood to the townsman. He is usually too lazy or too 【B13】______ to plant and look after new trees. So, 【B14】______ the government has a good system of control, or can educate the people, the forests slowly disappear.

This does not only mean that the villagers' sons and grandsons have 【B15】______ 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 the soil, thus preventing 【B16】______ washed away on the surface, causing floods and carrying 【B17】______ ground away 【B18】______ it the rich top-soil, in which crops grow so well. When all the top-soil is 【B19】______ , nothing remains 【B20】______ worthless desert.

A．with

B．at

C．in

D．through

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第6题

The elephant is the only animal in the world with a trunk （the very long nose of an elepha

The elephant is the only animal in the world with a trunk (the very long nose of an elephant), It uses its trunk【21】many ways. It【22】leaves off trees with its trunk and then puts them into its【23】. It can even uses its trunk to pull up trees when it wants to make a path through a jungle (热带丛林). It also uses its trunk to get【24】. The trunk can hold a lot of it,【25】an elephant needs to drink more than three hundred pints(品脱) of water every day. It has been easy for men to train elephants. All the elephants are considered useful in India【26】for white elephants. They are used to carry things for long distance in Indian forests. Many people say that some ancient Indian kings used to give white elephants to people they did not like. These white elephants were regarded as【27】animals. They could not be gave【28】to work. A person who owned a white elephant had to【29】a lot of money to keep it properly. After a certain time, he usually became very【30】. Nowadays people in England call a useless thing "a white elephant".

(56)

A．in

B．with

C．by

D．of

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第7题

Only those who can to lose their money should？

Only those who can to lose their money should make high-riskinvestments.

A) afford B) endure C) sustain D) maintain

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第8题

You should take only one at___time.

A.x

B.the

C.one

D.a

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第9题

All the useful energy at the surface of the earth comes from the activity of the sun. The

sun heats and feeds creatures and mankind. Each year it provides men with two hundred million tons of grain and nearly ten million tons of wood.

Coal, oil, natural gas, and all other fuels are stored energy from the sun. Some was collected by this season's plants as carbon compounds. Some was stored by plants and trees ages ago. Even waterpower derives from the sun. Water turned into vapor by the sun falls as rain. It courses down the mountains and is converted to electric power. Light transmits only the energy that comes from the sun's outer layer, and much of this energy that is directed towards the earth never arrives. About nine tenths of it is absorbed by the atmosphere of the earth. In fact, the earth itself gets only one half millionth of the sun's entire output of radiant energy.

The sun is the source of all of the following EXCEPT______.

A．gasoline

B．natural gas

C．atomic power

D．animal fat

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第10题

Exams, grades and marks should be abolished because children's progress should be estimate

d only by ______.

A．educated persons

B．the children themselves

C．teachers

D．parents

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第11题

All the useful energy at the surface of the earth comes from the activity of the sun. The

sun heats and feeds creatures and mankind. Each year it provides men with two hundred million tons of grain and nearly ten million tons of wood, coal, oil, natural gas, and all other fuels are stored energy from the sun. (80) Some was collected by this season' s plants as carbon compounds. Some was stored by plants and trees ages ago. Even waterpower derives from the sun. Water turned into vapor by the sun fails as rain. It courses down the mountains and is converted to electric power. Light transmits only the energy that comes from the sun' s outer layer, and much of this energy that is directed towards the earth never arrives. About nine tenths of it is absorbed by the atmosphere of the earth. In fact, the earth itself gets only one half millionth of the sun's entire output of radiant energy.

The sun is the source of all of the following EXCEPT______.

A．gasoline

B．natural gas

C．atomic power

D．animal fat

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