Trees should only be pruned (修剪, 整枝) when there is a good and clear reason for doing s - 试题答案网问答

第1题

听力原文：Windbreaks are barriers formed by trees and other plants. Farmers plant these bar

听力原文： Windbreaks are barriers formed by trees and other plants. Farmers plant these barriers around their fields to protect their land.

Windbreaks stop the wind from blowing soil away (33) . They also keep the wind from destroying or damaging crops. They are very important for protecting grain crops.

There have been studies done on windbreaks in parts of West Africa, for example. These found that grain harvests can be twenty percent higher in fields protected by windbreaks compared to fields without such protection (33) .

But windbreaks seem to work best when they allow some winds to pass through them (341. If the wall of trees and plants blocks the wind completely, then violent air motions will take place close to the ground. These motions will lift soil into the air where it will be blown away.

There should be at least two lines in each windbreak. one line should be large treas. The second line, right next to it, can be shorter trees and other plants with leaves. Locally grown trees and plants are best for windbreaks.

If the quality of the land is not very good, studies have shown that one kind of tree that can grow well is the white pine (35) .

Windbreaks not only protect land and crops from the wind. Surplus trees can be cut down and used to provide wood (33) .

(34)

A．They can prevent soil from being blown away.

B．They can improve the yield of crops.

C．They can provide wood when cut down.

D．They can protect crops from the strong sunshine.

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第2题

听力原文：The national forestry industry has seen a large increase in the demand for lumber

over the last 12 months. According to forestry statistics, revenues increased by 21 percent to $1.2 billion. The main reason for this increase has been due to the rise in home construction. This has resulted in a shortage of workers in the forestry sector. However, this shortage of workers should be resolved within the next four months. Employees are earning more pay for their work compared to last year. The amount of trees planted last year was a record for the country. There is also healthy competition among lumber companies within the country that is expected to continue for the next two years. The only foreseeable threat to the lumber industry is the possibility of the spruce budworm infecting large forests and destroying trees. Fortunately, scientists and researchers believe the risk is minimal.

What is the main reason for the growth in forestry？

A．The shortage of workers in the industry.

B．The elimination of forestry regulations.

C．The increase in home construction.

D．The addition of new technologies.

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第3题

Tress should only be pruned when there is a good and clear reason for doing so and , the

Question 26 to 30 are based on the following passage .

Tress should only be pruned when there is a good and clear reason for doing so and , the number of such reasons is small . Pruning involves the cutting away of overgrown and unwanted branches , and the inexperienced gardener can be encouraged by the thought that more damage results from doing it unnecessarily than from the tree to grow in its own way .

First , pruning may be done to make sure that trees have a desired shape or size . The object may be to get a tree of the right height , and at the same time 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 heavier . You may cut out diseased or dead wood , or branches that are rubbing against each other and thus cause wounds . The health of a tree may be encouraged by removing branches that are blocking up the center 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 for disease , 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 , so that there is a period when the tree is at risk . It should be the aim of every gardener to reduce that risk of death as far as possible . It is essential to make the area , which has been pruned smooth , and clean , for healing will be slowed down by roughness . You should allow the cut surface to dry for a few hours and then paint it with one of the substances available from garden shops especially for this purpose . Pruning is usually done in winter , for then you can see the shape of the tree clearly without interference from the leaves and also it is very unlikely that the cuts you make will bleed . If this does happen , it is , of course , impossible to paint them properly .

26. Pruning should be done to _____.

A)make the tree grow taller . B) does not protect them form. the wind

C)get rid of the small branches D) make the small branches thicker .

27. Trees become unhealthy if the gardener_______

A)allows too many branches to grow in the middle

B)does not protect them from the wind

C)forces them grow too quickly

D)damages some of the small side branches.

28 . Why is a special substance painted on the tree ？

A)to make a wound smooth .

B)to prevent disease entering a wound .

C)to cover a rough surface .

D) to help a wound to dry .

29. A good gardener prunes tree ____

A) at intervals throughout the year

B) as quickly as possible

C) occasionally when necessary

D) regularly every winter

30 . What was the author’s purpose when writing this passage ？

A)to give practical instruction for pruning a tree

B)to give a gardener description of pruning

C)to explain how trees develop disease

D)to discuss different methods of pruning

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第4题

The vllalge seemed deserted, the only sign of life()some trees waving in the howling wi

The vllalge seemed deserted, the only sign of life（)some trees waving in the howling wi

nd.

A.were

B.being

C.was

D.to be

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第5题

The word conservation has a thrifty meaning. To conserve is to save and protect, to leave

what we ourselves enjoy in such good condition that others may also share the enjoyment. Our forefathers had no idea that human population would increase faster than the supplies of raw materials; most of them, even until very recently, had the foolish idea that the treasures were "limitless" and "inexhaustible". Most of the citizens of earlier generations knew little or nothing about the complicated and delicate system that runs all through nature, and which means that, as in a living body, an unhealthy condition of one part will sooner or later be harmful to all the others.

Fifty years ago nature study was not part of the school work; scientific forestry was a

new idea; timber was still cheap because it could be brought in any quantity from distant woodlands; soil destruction and river floods were not national problems; nobody had yet studied long-term climatic cycles in relation to proper land use; even the word "conservation" had nothing of the meaning that it has for us today.

For the sake of ourselves and those who will come after us, we must now set about repairing the mistakes of our forefathers. Conservation should, therefore, be made a part of everyone's daily life. To know about the water table in the ground is just as important to us as a knowledge of the basic arithmetic formulas. We need to know why all watersheds need the protection of plant life and why the running current of streams and rivers must be made to yield their full benefit to the soil before they finally escape to the sea. We need to be taught the duty of planting trees as well as of cutting them. We need to know the importance of big, mature trees, because living space for most of man's fellow creatures on this planet is figured not only in square measure of surface but also in cubic volume above the earth. In brief, it should be our goal to restore as much of the original beauty of nature as we can.

According to the author, the greatest mistake of our forefathers was that______.

A．they had no idea about scientific forestry

B．they were not aware of the significance of nature study

C．they had little or no sense of environmental protection

D．they had no idea of how to make good use of raw materials

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第6题

Hill slopes were cleared of trees to make way for crops, but this only ______ the crisis.A

Hill slopes were cleared of trees to make way for crops, but this only ______ the crisis.

A．preceded

B．prevailed

C．ascended

D．accelerated

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第7题

The word conservation has a thrifty （节俭的) meaning. To conserve is to save and protect,

The word conservation has a thrifty (节俭的) meaning. To conserve is to save and protect, to leave what we ourselves enjoy in such good condition that others may also share the enjoyment. Our forefathers (祖先) had no idea that human population would increase faster than the supplies of raw (天然的) materials; most of them, even until very recently, had the foolish idea that the treasures were "limitless and inexhaustible". Most of the citizens of earlier generations knew little or nothing about the complicated (复杂的), and delicate system that runs all through nature, and which means that, as in a living body, an unhealthy condition of one part will sooner or later be harmful to all the others.

Fifty years ago nature study was not part of the school work; scientific forestry was a new idea; timber was still cheap because it could be brought in any quantity from distant woodlands; soil destruction and river floods were not national problems; nobody had yet studied long-term climatic cycles in relation to proper land use; even the word "conservation" had nothing of the meaning that it has for us today.

For the sake of ourselves and those who will come after us, we must now set about repairing the mistakes of our forefathers. Conservation should, therefore, be made a part of everyone's daily life. To know about the water table in the ground is just as important to us as a knowledge of the basic arithmetic formulas. We need to know why all watersheds need the protection of plant life and why the running current of streams and rivers must be made to benefit the soil fully before they finally escape to the sea. We need to be taught the duty of planting trees as well as of cutting them. We need to know the importance of big, mature trees, because living space for most of man's fellow creatures on this planet is figured not only in square measure of surface but also in cubic volume(立方)above the earth. In brief, it should be our goal to restore as much of the original (原始的) beauty of nature as we can.

The author's attitude towards the present situation in the use of natural resources is______.

A．positive (支持的)

B．neutral (中立的)

C．suspicious (怀疑的)

D．critical (批评的)

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第8题

The seeds of trees, grass and flowersA．are brought by wind and birds to the coral islands.

The seeds of trees, grass and flowers

A．are brought by wind and birds to the coral islands.

B．are brought by wind only to the coral islands.

C．are brought by people to the coral islands.

D．are brought by fishes to the coral islands.

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第9题

Which is the author's suggestion about vegetable gardening？A．One should have a large garde

Which is the author's suggestion about vegetable gardening？

A．One should have a large garden near home.

B．There should be fewer trees around the garden.

C．All gardening tasks should be done in spare time.

D．A small garden should be better-planned than a larger one.

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第10题

How do botanists know that root pressure is not the only force that moves water in plants？

A．Some very tall trees have weak root pressure.

B．Root pressures decrease in winter.

C．Plants can live after their roots die.

D．Water in a plant's roots is not connected to water in its stem.

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