The more forests were publicly held, the more welfare a society got.

A．much smaller

B．much more

C．much larger

D．many more

Passage Four

The atmosphere and oceans are not the only parts of the environment being damaged. Rain forests are being quickly destroyed as well, and their survival is questionable. E. O. Wilson, a biologist at Harvard, calls the depletion(枯竭、耗尽)of rain forest areas "the greatest extinction since the end of the age of dinosaurs(恐龙)."

Unlike some environmental issues, rain forests' depletion has fortunately received significant public and media's attention. Despite the opposition to the cutting down of rain forests, the problem continues. Every year, Brazil chops down an area of forests the size of the state of Nebraska. In addition to the Amazon's rain forests, many other forests are being cut down as well.: In Indonesia, Zaire, Papua-new Guinea, Malaysia, Burme, the Philippines, Peru, Colombia, Bolivia, and Venezuela, rain forests that were once great have been lost.

According to some estimates, 50 million acres of rain forest are cut down every year. The United Nations says the figure is closer to 17 million acres. The World Wildlife Fund says that every minute,25 to 50 acres are cut down or burnt to the ground.

The world's growing population has been a primary reason of rain forests' destruction. More people need land to live on and wood products to consume. Limiting population growth may be the first in a series of steps that would alleviate the destruction of the rain forests.

48. In the opinion of the author, ______are being destroyed terribly at present.

A. the oceans

B. the atmosphere

C. the rain forests

D. all the above

The ARPANET(66)(the rules of syntax that enable computers to communicate on a network)were originally designed for openness and flexibility, not for(67)The ARPA researchers needed to share information easily, so everyone needed to be an unrestricted "insider" on the network. Although the approach was appropriate at the time, it is not one that lends itself to today's commercial and government use.

As more locations with computers(known as(68)in Internet parlance)joined the ARPANET, the usefulness of the network grew. The ARPANET consisted primarily of university and government computers, and the applications supported on this network were simple: electronic mail(E - mail), electronic news groups, and(69)connection to other computers. By 1971, the Internet linked about two dozen research and government sites, and researchers had begun to use it to exchange(70)not directly related to the ARPANET itself. The network was becoming an important tool for collaborative research.

A．protocols

B．statute

C．law

D．enactment

In looking at the class structure of an entire system, we may find that its inheritance (1) is either wide and shallow, narrow and deep, or balanced. Class structures that are wide and shallow usually represent forests of (2) classes that can be mixed and matched. Class structures that are narrow and deep represent trees of classes that are related by a common ancestor. There are advantages and disadvantages to each approach. Forests of classes are more loosely (3) , but they may not exploit all the commonality that exists. Trees of classes exploit this commonality, so that individual classes are smaller than in forests. However, to understand a particular class, it is usually necessary to understand the meaning of all the classes it inherits from or uses. The proper shape of a class structure is highly problem-dependent. We must make similar trade-offs among inheritance, aggregation, and using relation- ships. For example, should the class Car inherit, contain, or use the classes named Engine and Wheel？ In this case, we suggest that an (4) relationship is more appropriate than inheritance relationship. Meyer states that between the class A and B," (5) is appropriate if every instance of B may also be viewed as an instance of A. The client relationship is appropriate when every instance of B simply possesses one or more attributes of A". From another perspective, if the behavior. of an object is more than the sum of its individual parts, then creating an aggregation relationship rather than an inheritance relationship between the appropriate classes is probably superior.

A．distinction

B．level

C．grade

D．hierarchy

Passage 2

When you think about the growth of human population over the last century or so, it is all too easy to imagine it merely as an increase in the number of humans. But as we _1_, so do all the things associated with us, including our livestock. At present, there are about 1.5 billion _2_ and domestic buffalo and about 1.7 billion sheep and goats. With pigs and poultry, they form. a _3_ part of our enormous biological footprint upon this planet. Just how enormous was not really _4_ until the publication of a new report, called “Livestock’s Long Shadow,” by the Food and Agriculture Organization of the United Nations. Consider these numbers. Global livestock grazing and feed production use “30 percent of the land surface of the planet.” Livestock—which consume more food than they _5_—also compete directly with humans for water. And the drive to expand grazing land destroys more biologically sensitive land, rain forests _6_, than anything else. But what is even more striking, and _7_, is that livestock are responsible for about 18 percent of the global warming effect, more than transportation’s _8_. Greenhouse gases, such as methane and nitrogen，are resulted from their digestion. Grazing land, which destroys forests, adds to the effect. There are no easy trade-offs when it comes to global warming—such as cutting back on livestock to make room for care. The human _9_ for meat is certainly not about to end anytime soon. As “Livestock’s Long Shadow” makes clear, our health and the health of the planet depend on pushing livestock production in more _10_ directions.

A)yield

B)contribution

C)stain

D)ideally

E)apparent

F)multiply

G)cattle

H)passion

I)scrape

J)critical

K)liable

L)sustainable

M)deposit

N)alarming

O)especially

第1空答案是：

The Smokey Bear(护林熊) fire prevention program has resulted in a savings of $20 billion on all federal(联邦的), state and private forested land(私有林地). In 1941, 208,000 forest fires burned 30 million acres, while in 1981, fewer than 165,000 fires burned about three million acres. While forest usage has increased, the proportion(比例) of human-caused fires has remained stable; people still cause nine out of ten forest fires. But the biggest cause of fires is arson(纵火), accounting for(引起) 34 percent of forest fires in 1981.

1. According to the passage, use of forested land has ____.

A、stabilized

B、been privatized

C、decreased

D、risen

2. According to the passage, in 1941 forest fires burned ____.

A、less acres than in 1981

B、3 million acres

C、ten times as many acres as in 1981

D、20 million acres more than in 1981

3. According to the passage, the number of human-caused fires ____.

A、has remained the same proportionately

B、has increased

C、is the same as the arson cases

D、accounts for 34 per cent of forest fires

4. According to the passage, which of the following statements is true？

A、Nine out of ten fires are caused by arsonists.

B、The Smokey Bear program has saved the nation a lot of money.

C、There are more forest fires now than before.

D、People do not use the forests as much as they did in the past.

5. It may be inferred from the passage that ____.

A、the majority of fires are caused by humans

B、arson is increasing every year

C、more acres are destroyed by fire each year

D、fewer people are using the forests

【C1】______protecting the soil, providing water and【C2】______the climate. Trees【C3】______soil to mountainsides. Hills【C4】______the trees have been felled lose 500 times as【C5】______soil a year as those with trees.

Trees catch and【C6】______rainwater. Their leaves break the impact【C7】______the rains, robbing them of【C8】______destructive power. The roots of trees allow the water to go into the soil,【C9】______gradually releases it to flow down rivers and refill ground-water reserves. Where there are no【C10】______, the rains run in sheets of water off the land,【C11】______the soil with there Land【C12】______with trees and other plants【C13】______20 times more rainwater than【C14】______earth. As they grow, trees absorb carbon dioxide, the main【C15】______of the "greenhouse effect", which【C16】______irreversibly to change the world's climate. Together, the world's trees, plants and soils contain three times as much carbon as【C17】______is in the atmosphere.

The world's forests【C18】______the vast majority of its animal and plant species. The tropical rainforests【C19】______have well over half of them,【C20】______they cover only about 6% of the Earth's land surface.

【C1】

A．for

B．from

C．by

D．with

flowers.There are 175 different kinds oftrees, and 60 kinds of birds live here. (46) You are down-town in the city of Nara,Japan,in Kasugayama Forest, the oldest urban forest in theworld. It wasstarted more than a thousand years ago, and today it's verypopular with tourists and artists.

Citiesaround the world are working to protect their urban forests. Some urban forestsare parks, andsome are just streets with a lot of trees. But all urban forestshave many good effects on the environment. (47) They also stop the noisefrom heavy traffic. They even make the weather better because theymake the air3-5 degrees cooler, and they stop strong winds.

Urbanforests also have many good effects on people. They make the city morebeautiful. In a crowded ar-ea, they give people a place to relax and spend timein nature. (48)

In somecountries, people are starting new urban forests. InEngland,there are now l. 3 milliontrees in an urban forest called Thames Chase, east ofLondon. It wasstarted in 1990, and it has grownvery fast. Walking and bicycle clubs use theforest, and there are programs for children and artists. (49)

Someolder cities don't have space for a big urban forest, but planting trees on thestreets makesthe city better. Scientists found that commuters (通勤人员) feel more relaxedwhen they can see trees.Trees are even good for business. _ (50)In the future, urban forests willbecome even moreimportant as our cities grow bigger. In the megacities (超大城市) of tomorrow, peoplewill need moregreen space to live a comfortable life. Planting trees today willmake our lives better in the future.

A.Peoplespend more time at shopping centers that have trees.

B. In hot countries, urban forests are coolplaces for walking and other healthy exercises.

C.Butyou are not in rural area.

D.Trees take pollution out of the air

E.In2033, it will have 5 million trees.

F.It has many kinds of birds in the country