Special Training of Explanatory Writing in Junior High School (Part)

Lemmings are the oldest animals on the Arctic grassland. Their fertility rate is too fast. They can produce up to 20 at a time and mature in 20 days. If a pair of mice and people devote themselves to family planning from spring, they will produce hundreds of thousands of offspring in autumn. Every three or four years, the number of lemmings will be large enough to eat up everything that can be eaten on the grassland. At this time, they have to consider future generations, how to eliminate the surplus? Death! Active death is the best way.

At this time, lemmings suddenly changed from gray-black to bright orange, exposing their own places and attracting natural enemies to hold belly burials for themselves. But foxes and owls not only try their best to eat all the lemmings.

So the lemmings gathered together, and hundreds of millions of lemmings began the most miserable journey of their lives in droves. They rushed to the sea, and the lemmings in front used their bodies to bridge rivers and ponds in the water, while the lemmings in the back stepped on the bodies of the same kind to move on. Wherever the army went, all the plants were eaten up and the grassland became a wasteland. After their death team came to the seaside, millions of lemmings hugged each other and rolled in the water like hills. ...

The origin of lemmings' name is because of this death journey. Pitek of the United States explained the lemmings' suicide with the theory of nutritional recovery: when the number of rodents reached its peak, vegetation was destroyed due to overeating, food was insufficient, and hidden conditions deteriorated, and all but a few had to die. When plants recover, their numbers will rise again.

16. According to the context, talk about the meanings of the following additional words in the text. (4 points)

(1) If a pair of mice and people start to devote themselves to family planning in spring, they will produce hundreds of thousands of offspring in autumn.

Manufacturing industry: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

(2) Expose your own place and attract natural enemies to hold belly burials for yourself.

Abdominal burial: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

17. From the introduction of this article, what are the characteristics of lemmings? (3 points)

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18. What are two ways for lemmings to die voluntarily? (2 points)

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19. Can we get some valuable enlightenment from the active death of lemmings? Please talk about your thoughts. (4 points)

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(Changde City, 2005)

answer

16.( 1) Rapid propagation (mass birth) (2 points) (2) Lemmings are eaten by natural enemies and buried in their stomachs. (2 points)

17. Strong fertility (fast reproduction); Great damage to vegetation; Take the initiative to die if there are too many.

18. first, turn it into a striking color to attract natural enemies to eat themselves (hold a belly burial for themselves); Second, the group ran to the sea and drowned.

19. Key points: ① The spirit of unity, no hesitation and no fear of sacrifice in collective behavior is worthy of recognition. In order to survive in the future, mankind should take the initiative to prevent the deterioration of some hidden conditions. When the disaster comes, it is necessary to sacrifice some interests actively. (Answer only one of them)

New technology on the road

For a long time, the urban pavement in China is either "black" or "white" (black asphalt and white cement), but in Europe, such as Britain, Germany, the Netherlands and other countries, colored pavement is more popular. Through different road colors, such as red, green, blue, yellow and so on. Remind drivers of different vehicles to drive on designated roads to avoid mixed traffic and greatly improve safety.

Now, some cities in China have begun to adopt colored pavements. Take Beijing as an example. When the car drives to the corner from Yonghe Palace to Dongzhimen on the Second Ring Road, it will find that the road surface here is different from other places. One is dark red, which turned out to be an accident-prone place. Change the color of the road to attract the driver's attention; Second, the pavement is covered with a layer of granular anti-slip material. In some parts of Shanghai, there are also bright green and orange roads, and all kinds of vehicles "go their own way". This kind of colored pavement not only beautifies the city appearance, but also plays an anti-skid role, prompting drivers to slow down to reduce traffic accidents and facilitate traffic management.

At the same time, a novel porous asphalt permeable pavement came into being. Adopting this paving technology which can absorb and recycle rainwater is undoubtedly good news for cities lacking water. This technology makes asphalt pavement into "three layers": the top layer is provided with permeable materials, the middle layer is provided with rainwater diversion facilities to divert rainwater from the top layer to the drainage pipe for recycling, and the bottom layer is a sealing layer to prevent rainwater from infiltrating into the ground.

Permeable pavement is a mixture of reinforced fibers added to ordinary asphalt, which increases the porosity of pavement from about 4% of ordinary asphalt pavement to 15%-25%, and some even as high as 30%, greatly improving the ability of pavement to absorb rainwater. The characteristics of this material also determine that its service life is longer than that of traditional pavement, because it can avoid the damage of pavement material structure caused by pavement icing in winter. In addition, when it rains, this kind of road surface does not accumulate water or splash water, and the car is not easy to slip when driving, which is beneficial to traffic safety.

At present, in Europe, the permeability of permeable pavement has reached 15%- 18%. Germany plans to transform 90% of urban pavements into permeable pavements before 20 10. This technology should also be vigorously promoted in cities where water shortage is common in China.

(Selected from Encyclopedia Knowledge, No.3, 2005, with deletion)

14. In the second paragraph, "The road surface here is different from other places". What two aspects do you mean by "different"? Which sentence in the paragraph 1 means "each goes his own way"? (4 points)

15. Read the second and third paragraphs and choose a question to answer. (3 points)

(1) What are the three functions of the colored pavement in the second paragraph? Please summarize it briefly. (No more than 20 words)

(2) The permeable pavement mentioned in paragraph 3 is divided into three layers. What is the function of each layer? Please sum it up in two words.

16. What do the last two paragraphs mainly explain? Please summarize it briefly. (2 points)

17. According to the information provided in the article, one of the following statements is correct (3 points) ().

A. At present, some big cities such as China, Beijing and Shanghai are basically paved with colored pavements.

B The void ratio of ordinary asphalt pavement is less than 4%, while that of permeable pavement is 15%-30%.

C. There are similarities between colored pavement and permeable pavement, both for improving traffic safety.

D. Due to the advantages of permeable pavement, Germany has transformed 90% of the country's pavement into permeable pavement.

(Yancheng City, Jiangsu Province, 2005)

answer

14. color (or "dark red") and material (or "the road surface is covered with a layer of granular anti-skid material") (2 points) to remind drivers of different vehicles to drive on the designated road surface (2 points).

15.( 1) ① beautify the city (1)

② Reduce traffic accidents (or "prevent skidding and prompt drivers to slow down") (1)

③ Convenient traffic management (1 min) (every 3 deductions 1 min)

(2)① Infiltration (1) ② Diversion (or "recovery") (1) ③ Sealing (or "seepage prevention") (1)

(If you do both questions, give the better answer) (3 points)

16. Explain the characteristics and development trend of permeable pavement (one aspect is given 1 minute) (2 points if the meaning is correct).

17.c (3 points)

Watch out, silent soil killer

Soil, water, sunlight and air are the four elements of life on earth. General pollution can immediately attract public attention, while soil pollution is invisible, and its adverse consequences will not appear until months, years, decades or even hundreds of years later. Different from air or water pollutants, soil pollution can directly enter the human body and endanger health, but indirectly affect human health. Because pollutants in the soil enter the human body through the food chain, mainly through food, vegetables, fruits, milk, eggs, meat and so on. Some places often do not pay attention to the remediation of soil pollution. However, soil pollution lasts longer than other pollution, and pollutants are not as easy to spread and dilute as in air and water. After long-term accumulation, its impact is often regional, heavy metal pollution is basically an irreversible process, and it may take a long time for contaminated soil to return to normal.

In recent years, due to the rapid growth of population and the rapid development of industry, solid wastes are piled up and dumped on the soil surface, harmful wastewater seeps into the soil, and harmful gases and floating dust in the atmosphere continue to fall into the soil with rainwater, resulting in soil pollution. Fertilizers, pesticides and unqualified manure used in agricultural production are also important sources of soil pollution. In addition, chemical residues such as explosives and heavy metals after the war also caused serious damage to the soil in the war zone. Researcher Chen pointed out that 90% of the pollutants in the world eventually entered the soil.

Recently, it is estimated that more than 6,543,800 hectares of cultivated land in China are polluted, accounting for one fifth of the total cultivated land in the world, including 2 million hectares of land polluted by mining areas, 5 million hectares of land polluted by oil and 50,000 hectares of land polluted by solid waste. Every year, grain production is reduced by more than 65.438 million tons due to soil pollution, and all kinds of agricultural economic losses caused by soil pollution total 20 billion yuan.

Soil pollution has threatened human health. Researcher Chen spent three years sampling and analyzing the soil and vegetables in Beijing on a large scale, and found that the problem of soil pollution is becoming more and more serious, which has affected the quality of agricultural products such as vegetables. Soil pollution will make pollutants accumulate in plants, enrich into people and animals through the food chain, endanger human and animal health and cause various diseases. Soil pollution can also lead to other environmental problems.

(Selected from Nature and Man, with changes)

13. What are the different characteristics of soil pollution compared with other pollutants? (3 points)

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14. There are many kinds of soil pollutants, two of which are listed below. Please find others from the text and describe them according to examples. (3 points)

Example: (1) Fertilizer, pesticide and unqualified excrement spread on crops.

(2) Explosives, heavy metals and other chemicals remaining in the soil.

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15. What do you think the data cited in the third paragraph does? Please briefly explain the specific content. (3 points)

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16. After reading this essay, you must have a new understanding of soil pollution. Please put forward a suggestion to prevent soil pollution or draw up a warning slogan according to your usual observation and thinking. (3 points)

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(Zhoushan City, Zhejiang Province, 2005)

answer

13.( 1) Soil pollution is intangible (2) It indirectly affects human health (3) The pollution lasts longer.

14.( 1) Solid waste piled up and dumped on the soil surface (2) harmful waste water seeping into the soil (3) harmful gas and floating dust falling into the soil (together with rainwater).

15. The seriousness of soil pollution in China and the huge losses caused by it are explained concretely and accurately.

16. (The answer to this question is open, as long as it can be written around the main points of preventing soil pollution and warning people to protect soil. )