摘要: was/is not certain 提升练习

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Have you ever noticed the colour of the water in a river or stream after a heavy rainfall? What do you think caused this change in colour? It is soil that has been washed into the river from the riverbank or from t}le nearby fields.

Components of Soft

Soil is made up of a number of layers(层),each having its own distinctive colour and texture.The upper layer is known as the litter.It acts like a blanket.limiting temperature changes and reducing water loss.The topsoil layer is made up of small particles of rock mixed with rotten plant and animal matter called humus(腐殖质),which is black and gives the topsoil its dark colour.This layer is usually rich in nutrients,oxygen,and water.Below the topsoil is the subsoil,a layer that contains more stones mixed with only small amounts of organic matter.This layer is lighter in colour because of the lack of humus.Beneath the soil lies a layer of bedrock.

Soil forms from the bottom up.Over time bedrock is attacked by rain, wind,frost, and snow.It is gradually broken down into smaller particles in a process called weathering.Plants begin to grow,and rotten materials enrich the topsoil.Most of the soil in Eastern Canada.for example.Was formed from weathered rock that was exposed when the ice disappeared l2.000 years ag0.

Water Beneath the Soil

Surface water collects and flows above the ground in lakes.ponds.and rivers.Once in the soil or rock,it is called groundwater.Gravity pulls groundwater through the soil in a process called percolation(渗透).Eventually the water reaches a layer called the water table.Under this is bedrock through which water cannot percolate.

As water percolates downward,it dissolves organic matter and minerals from the soil and carries them to deeper layers.This causes a serious problem because plants require these nutrients for growth.

Soil pH

Soil can be acidic.neutral.or basic.The pH of the soil is determined by the nature of the rock

from which it was formed.and by the nature of t}le plants that grow and rot in it.

The acidity of rain and snow can lower the pH of the groundwater that enters the soil.By burning fossil fuels such as coal,oil and gasoline,humans have been contributing to higher levels of acidity in many soils.When fossil fuels are burned.gases are released into the air and then fall back to earth as acid rain.Acid soil increases出e problem of carrying nutrients to lower soil levels.As nutrients are removed,soil is less fertile.Plants grow more slowly in acidic soil,and also become easily attacked by diseases.

67.The layer of soil that provides necessary nutrients for plant growth is called.

A.1itter    B.topsoil    C.humus D.subsoil

68.According to the text.which of the following is NOT true?

A.Soil forms from weathered rock on the earth surface.

B.The deeper layer of soil is darker in colour than t}le surface soil.

C.Air pollution is partially responsible for acid soil.

D.Groundwater tends to carry away nutrients for plant growth.

69.We can infer from the passage that the water table lies       .

A.between the topsoil layer and the subsoil layer

B.in the subsoil layer above bedrock

C.between the subsoil layer and bedrock

D.in the bedrock layer beneath the subsoil

70.The underlined word “dissolve” is used to express the idea that organic matter and minerals from soil are          .

A.rushed away into the river

B.cleaned and purified by water

C.destroyed and carried away by water

D.mixed with water and become part of it

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This was no ordinary class. The students who came together were all science or engineering professors at Cornell University. They had interrupted their research to accept an invitation to take part in an unusual experiment: “an interesting week of poetry.” This class was part of a study to answer the questions: Why is science difficult for many nonscience students? What can teachers learn about teaching if they take a class that is not in their field?

The students in the poetry class listened to lectures and took notes. They had reading tasks and had to write three short papers. All students noticed one thing – the importance of spoken words. In science and engineering classes, the instructors put tables and drawings on the blackboard. But in this poetry class, the instructors just talked. They didn’t write anything on the board.

The scientists and engineers noticed one similarity between science and poetry. In both subjects, students need to find layers (层次) of meaning . Some layers are simple, clean, and on the surface; other layers are deeper and more difficult. This search for different levels of meaning doesn’t happen much in undergraduate(本科) science classes, but it is important later, in graduate school. And it is always important in humanities(人文科学).

Both the poetry instructors and their students learned something about teaching from this experience. One poetry instructor, for example, now sees the importance of using informative as he teaches. Most of the scientists agreed on several points. First, humanities classes might help science students to see patterns and decide which information is important. Second, the poetry class was fun. One engineer decided, “We need to change the way we teach engineering to make to make it an enjoyable experience for students.”

But perhaps the most important result of the experience was this; All of the professors began to think about how they teach and how they cam teach better.

What do we know about this unusual class?

A. The teachers did lots of writing on the board

B. The teacher were invited to attend several lectures.

C. The student were professors from a university

D. The students were studying science and humanities.

The experiment was designed to find out              

   A. how to teach the students in the science class

B. whether poetry is difficult for science students

C. what to be taught in the humanities class

D. why many humanities students find science hard.

Finding levels of meaning is            .

   A. important for graduate students in humanities

B. difficult for graduate students in humanities

C. common for undergraduate students in science

D. easy for undergraduate students in science.

What did the science professors learn after the experiment?

   A. They should change the way they teach

B. A poem could be explained in clear definitions.

C. A poetry class could be more informative.

D. Their teaching was an enjoyable experience.

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A 26-year-old Montreal man appears to have succeeded in his quest to barter a single, red paper clip(夹子) all the way up to a house. It took almost a year and 14 trades, but Kyle MacDonald has been offered a two-storey farmhouse in Kipling, Sask., for a paid role in a movie.

MacDonald began his quest last summer when he decided he wanted to live in a house. He didn’t have a job, so instead of posting a resumé, he looked at a red paper clip on his desk and decided to trade it on an Internet website. The response was immediate —a fish pen was offered for exchange. MacDonald then bartered the fish pen for a handmade doorknob from a potter in Seattle.

In Massachusetts, MacDonald traded the doorknob for a camp stove. He traded the stove to a U.S. soldier in California for a generator. Then he exchanged the generator for an “instant party kit” — an empty keg(小桶) and an illuminated Budweiser beer sign. MacDonald then traded the keg and sign for a snowmobile. He bartered all the way up to an afternoon with rock star Alice Cooper, a KISS snow globe and finally a paid role in a Corbin Bernsen movie.

“Now, I’m sure the first question on your mind is, ‘Why would Corbin Bernsen trade a role in a film for a snow globe? A KISS snow globe,’ MacDonald said on his website.”Well, Corbin happens to be arguably one of the biggest snow globe collectors on the planet.

Now, the town of Kipling, Sask., Canada, with a population of 1,100, has offered MacDonald a farmhouse in exchange for the role in the movie. The town is going to hold a competition for the movie role.

MacDonald said: “There’re people all over the world that are saying that they have paper clips clipped to the top of their computer, or on their desk or on their shirt, and it proves that anything is possible and I think to a certain degree it’s true.”

MacDonald, who has attracted international media attention in his quest, said the journey has turned out to be more exciting than the goal. “This is not the end. This may be the end of this part of the story, but this story will go on.”

The best title for this passage is “    ”.

A.A lucky paper clip    B. From poor to rich

C.A lucky young man   D. From paper clip to house

The underlined word in line 1 means     .

A. to get something for free    B. to sell something at a price

C. to sell goods on the Internet  D. to exchange goods for other goods

Which shows the correct order of the trades?

A. Paper clip?snow globe?snowmobile?house

B. Paper clip?keg of beer?doorknob?snowmobile

C. Paper clip?camp stove?snowmobile?movie role

D. Paper clip?keg of beer?camp stove?snowmobile

Which statement about MacDonald’s trades is TRUE?

A. All of his trades were done in his country.

B.A film role was offered due to Bernsen’s hobby.

C. They took over a year and some of them were really unbelievable.

D. The house in Kipling has been offered to MacDonald to attract media.

What can we learn about MacDonald?

A. He wanted to gain fame through his quest.

B .His success largely depended on the Internet.

C. He never expected his aim could be achieved.

D. He intends to begin another quest on the Web.

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Remember how great exercise was when you were a little kid? Back then, racing around the playground or skipping rope for hours, you weren’t thinking fitness, you were thinking entertainment. But in this age of high-tech home equipment and underused gym memberships, the simple joy of jumping rope has been forgotten, Rediscovering it will give you a total-body exercise you can find.

    Although considered an excellent form of exercise, jumping rope has never gained widespread acceptance because of two fundamental reasons. First, most people recognize jumping rope as an excellent form of cardiovascular(心血管的)exercise, but they also believe that it is simply too difficult. In other words, they don’t think they’ll be able to continue jumping for the near 20 minutes that it takes to achieve a beneficial physical outcome. Second, many view it as somewhat boring and overly repetitive not as something fun or enjoyable.

     As a matter of fact, jumping rope can be great fun if you find a proper way to practice it. Instead of doing the usual two-foot bounce over and over again, people good at rope-jumping often change their pattern every 10 or 20 jumps. A single bounce, a double-bounce, a skip, a knee-up, side swings, as well as a variety of other easy-to-learn free-style rope-jumping.

     Now researchers are learning that jumping rope also prepares the brain for learning. It is an exercise allowing both brain hemispheres to perform in parallel to each other. In short, jumping rope can be a life-long activity requiring little equipment, time and space, yet leading to a much healthier life.

61. From the first paragraph we learn that_________.

A. jumping rope has faded from people’s memories

B. people now have more advanced equipment

C. racing around the playground was preferred

D. people now like to have exercise in a gym

62.Rope jumping has not spread widely because_________.

A. it benefits the cardiovascular system

B. it is neither easy nor enjoyable

C. it is considered boring and repetitive

D. it requires little equipment, time and space

63.The first sentence in the 3rd paragraph implies_________.

A. there is only one proper way to follow

B. the usual way should not be used

C. the easiest way is always the best

D. there are many ways to follow

64.According to the researchers, jumping rope_________.

A. only prepares the brain for learning

B. is suitable for students only

C. helps both brain hemispheres work together

D. can be dangerous for old people

65.What is the author’s attitude towards rope jumping?

A. He is arguing against it

B. He is in favor of it

C. He is sitting on the fence of it

D. He is not clear about it

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Money spent o advertising is money spent as well as any I know of. It serves directly to bring about a rapid sale of goods at reasonable prices, so setting up a firm home market and making it possible to provide for export at good prices is a good investment. By drawing attention to new ideas it helps greatly to raise standards of living. By helping to increase demand it causes an increased need for labour, and is therefore a nice way to fight unemployment. It lowers the costs of many services: without advertisements your daily newspaper would cost four times as much, the price of your television program would need to be doubled, and travel by bus or subway would cost more.

And perhaps most important of all, advertising provides a promise of reasonable value in the products and services you

buy. Besides the fact that twenty-seven Acts of Parliament govern the terms of advertising, no regular advertiser dare produce anything that fails to live up to the promise of his advertisements. He might fool some people for a little while through misleading advertising. He will not do so for long, for the public has the good sense not to buy the poor goods more than once. If you see product frequently advertised, it is the proof I know that the product does what is promised for it, and that it has good value.

Advertising does more for the good of the public than any other force I can think of.

There is one more point I feel I ought to touch on. Recently I heard a well-known television person declare that he was against advertising because it persuades rather than informs. He was telling us the real difference. Of course advertising tries to persuade.

If its message were nothing but information, that would be difficult to get more people to buy, for even the choice of the colour of a shirt is a bit persuasive (有说服力的) -advertising would be so boring that no one would pay any atten-tion. But perhaps that is what the well-known television person wants.

In the passage, which of the following is NOT included in the advantages of advertising?

A. Getting greater fame.  B. Providing more jobs. C. Raising living standards.  D. Reducing newspaper cost.

The writer thinks that the well-known TV person is ________ .

A. quite right in passing his judgment on advertising

B. interested in nothing but the buyers' attention

C. correct in telling the difference between persuasion and information

D. obviously unfair in his views on advertising

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