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Chinese Population Growth

Increases in population have usually been accompanied (indeed facilitated) by an increase in trade. In the Western experience, commerce provided the conditions that allowed industrialization to get started, which in turn led to growth in science, technology, industry, transport, communications, social change, and the like that we group under the broad term of “development.” However, the massive increase in population that in Europe was at first attributed to industrialization starting in the eighteenth century occurred also and at the same period in China, even though there was no comparable industrialization.

It is estimated that the Chinese population by 1600 was close to 150 million. The transition between the Ming and Qing dynasties (the seventeenth century) may have seen a decline, but from 1741 to 1851 the annual figures rose steadily and spectacularly, perhaps beginning with 143 million and ending with 432 million. If we accept these totals, we are confronted with a situation in which the Chinese population doubled in the 50 years from 1790 to 1840. If, with greater caution, we assume lower totals in the early eighteenth century and only 400 million in 1850, we still face a startling fact: something like a doubling of the vast Chinese population in the century before Western contact, foreign trade, and industrialization could have had much effect.

To explain this sudden increase we cannot point to factors constant in Chinese society but must find conditions or a combination of factors that were newly effective in this period. Among these is the almost complete internal peace maintained under Manchu rule during the eighteenth century. There was also an increase in foreign trade through Guangzhou (southern China) and some improvement of transportation within the empire. Control of disease, like the checking of smallpox by variolation may have been important. But of most critical importance was the food supply.

Confronted with a multitude of unreliable figures, economists have compared the population records with the aggregate data for cultivated land area and grain production in the six centuries since 1368. Assuming that China’s population in

1400 was about 80 million, the economist Dwight Perkins concludes that its growth to 700 million or more in the 1960s was made possible by a steady increase in the grain supply, which evidently grew five or six times between 1400 and 1800 and rose another 50 percent between 1800 and 1965. This increase of food supply was due

perhaps half to the increase of cultivated area, particularly by migration and settlement in the central and western provinces, and half to greater productivity—the farmers’ success in raising more crops per unit of land.

This technological advance took many forms: one was the continual introduction from the south of earlier-ripening varieties of rice, which made possible

double-cropping (the production of two harvests per year from one field). New crops such as corn (maize) and sweet potatoes as well as peanuts and tobacco were introduced from the Americas. Corn, for instance, can be grown on the dry soil and marginal hill land of North China, where it is used for food, fuel, and fodder and provides something like one-seventh of the food energy available in the area. The sweet potato, growing in sandy soil and providing more food energy per unit of land than other crops, became the main food of the poor in much of the South China rice area.

Productivity in agriculture was also improved by capital investments, first of all in irrigation. From 1400 to 1900 the total of irrigated land seems to have increased almost three times. There was also a gain in farm tools, draft animals, and fertilizer, to say nothing of the population growth itself, which increased half again as fast as cultivated land area and so increased the ratio of human hands available per unit of land. Thus the rising population was fed by a more intensive agriculture, applying more labor and fertilizer to the land.

Paragraph 1

Increases in population have usually been accompanied (indeed facilitated) by an increase in trade. In the Western experience, commerce provided the conditions that allowed industrialization to get started, which in turn led to growth in science, technology, industry, transport, communications, social change, and the like that we group under the broad term of “development.” However, the massive

increase in population that in Europe was at first attributed to industrialization starting in the eighteenth century occurred also and at the same period in China, even though there was no comparable industrialization.

1. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.

A. Commerce, industrialization, and development are common features of the Western

experience.

B. Trade, industrialization, and development accelerated social change in Western societies.

C. Trade and industrialization brought about development in Western societies.

D. In Western societies, social change provided the conditions for development in a number of areas.

2. The word “attributed” in the passage is closest in meaning to

A. accustomed

B. credited

C. exposed

D. transformed

Paragraph 1 and Paragraph 2

Increases in population have usually been accompanied (indeed facilitated) by an increase in trade. In the Western experience, commerce provided the conditions that allowed industrialization to get started, which in turn led to growth in science, technology, industry, transport, communications, social change, and the like that we group under the broad term of “development.” However, the massive increase in population that in Europe was at first attributed to industrialization starting in the eighteenth century occurred also and at the same period in China, even though there was no comparable industrialization.

It is estimated that the Chinese population by 1600 was close to 150 million. The transition between the Ming and Qing dynasties (the seventeenth century) may have seen a decline, but from 1741 to 1851 the annual figures rose steadily and

spectacularly, perhaps beginning with 143 million and ending with 432 million. If we accept these totals, we are confronted with a situation in which the Chinese population doubled in the 50 years from 1790 to 1840. If, with greater caution, we assume lower totals in the early eighteenth century and only 400 million in 1850, we still face a startling fact: something like a doubling of the vast Chinese population in the century before Western contact, foreign trade, and industrialization could have had much effect.

3. According to paragraphs 1 and 2, which of the following is true of Chinese population growth between 1741and 1851?

A. It coincided with the beginning of industrialization in China.

B. It prompted speculation about the actual number of people living in China in previous centuries.

C. It continued the steady growth in population of previous centuries.

D. It occurred in the absence of certain conditions generally associated with population growth.

4. According to paragraph2, the estimated population of China in the mid 1700s was ?

A. 143 million

B. 150 million

C. 400 million

D. 432 million

Paragraph 3

To explain this sudden increase we cannot point to factors constant in Chinese society but must find conditions or a combination of factors that were newly effective in this period. Among these is the almost complete internal peace maintained under Manchu rule during the eighteenth century. There was also an increase in foreign trade through Guangzhou (southern China) and some improvement of transportation within the empire. Control of disease, like the checking of smallpox by variolation may have been important. But of most critical importance was the food supply.

5. The word “constant ” in the passage is closest in meaning to

B. dominant

C. altered

D. unchanging

6. Paragraph 3 supports all of the following statements about eighteenth-century Chinese society EXCEPT:

A. It was troubled by frequent conflicts with foreign nations.

B. It improved its transportation system.

C. It experienced growth in international commerce.

D. It managed to prevent the spread of certain diseases.

Paragraph 4

Confronted with a multitude of unreliable figures, economists have compared the population records with the aggregate data for cultivated land area and grain production in the six centuries since 1368. Assuming that China’s population in 1400 was about 80 million, the economist Dwight Perkins concludes that its growth to 700 million or more in the 1960s was made possible by a steady increase in the grain supply, which evidently grew five or six times between 1400 and 1800 and rose another 50 percent between 1800 and 1965. This increase of food supply was due perhaps half to the increase of cultivated area, particularly by migration and settlement in the central and western provinces, and half to greater productivity—the farmers’ success in raising more crops per unit of land.

7. Para graph 4 answers which of the following questions about China’s population growth between 1400 and 1965?

A. Which figures relating to China’s population growth were unreliable?

B. Why did Dwight Perkins assume that China’s population in 1400 was about 80 million?

C. Where in China did most of the population increase take place?

D. What factors made China’s population growth between 1400 and 1965 possible?

8. The word “aggregate” in the passage is closest in meaning to

A. available

C. combined

D. recorded

Paragraph 5

This technological advance took many forms: one was the continual introduction from the south of earlier-ripening varieties of rice, which made possible

double-cropping (the production of two harvests per year from one field). New crops such as corn (maize) and sweet potatoes as well as peanuts and tobacco were introduced from the Americas. Corn, for instance, can be grown on the dry soil and marginal hill land of North China, where it is used for food, fuel, and fodder and provides something like one-seventh of the food energy available in the area. The sweet potato, growing in sandy soil and providing more food energy per unit of land than other crops, became

the main food of the poor in much of the South China rice area.

9. What can be inferred from paragraph 5 about the introduction of corn and sweet potatoes in China?

A. These crops required much more care than other crops.

B. These crops were consumed in limited quantities.

C. These crops permitted an expansion of the area used for farming.

D. These crops became available all over China within a short period of time. Paragraph 6

Productivity in agriculture was also improved by capital investments, first of all in irrigation. From 1400 to 1900 the total of irrigated land seems to have increased almost three times. There was also a gain in farm tools, draft animals, and fertilizer, to say nothing of the population growth itself, which increased half again as fast as cultivated land area and so increased the ratio of human hands available per unit of land. Thus the rising population was fed by a more intensive agriculture, applying more labor and fertilizer to the land.

10. The word “ratio” in the passage is closest in meaning to

A. proportion

B. availability

C. importance

D. cost

Paragraph 5 and Paragraph 6

This technological advance took many forms: one was the continual introduction from the south of earlier-ripening varieties of rice, which made possible

double-cropping (the production of two harvests per year from one field). New crops such as corn (maize) and sweet potatoes as well as peanuts and tobacco were introduced from the Americas. Corn, for instance, can be grown on the dry soil and marginal hill land of North China, where it is used for food, fuel, and fodder and provides something like one-seventh of the food energy available in the area. The sweet potato, growing in sandy soil and providing more food energy per unit of land than other crops, became the main food of the poor in much of the South China rice area.

Productivity in agriculture was also improved by capital investments, first of all in irrigation. From 1400 to 1900 the total of irrigated land seems to have increased almost three times. There was also a gain in farm tools, draft animals, and fertilizer, to say nothing of the population growth itself, which increased half again as fast as cultivated land area and so increased the ratio of human hands available per unit of land. Thus the rising population was fed by a more intensive agriculture, applying more labor and fertilizer to the land.

11. Which of the following is NOT mentioned in paragraphs 5 and 6 as one of the strategies the Chinese applied in agriculture?

A. The growing of two crops on the same field during the same year

B. The improvement of systems to supply crops with water

C. The application of increasing amounts of fertilizer to the land

D. The reduction in the amount of human labor per unit of land

12. What purpose does paragraph 5 serve in the larger discussion about China’s population growth?

A. It provides evidence of China’s emerging foreign trade relations.

B. It illustrates how the Chinese increased their food supply.

C. It provides evidence of why population growth was most noticeable in the south.

D. It shows how foreign crops gradually gained greater acceptance in China.

13.Look at the four squares [■] that indicate where the following sentence could be added to the passage.

Other developments addressed the problems of dry and sandy areas unsuitable for growing China’s native crops.

Where would the sentence best fit? Click on a square [■] to add the sentence to the passage.

This technological advance took many forms: one was the continual introduction from the south of earlier-ripening varieties of rice, which made possible

double-cropping (the production of

two harvests per year from one field). ■ New crops such as corn (maize) and sweet potatoes as well as peanuts and tobacco were introduced from the Americas.

■Corn, for instance, can be grown on the dry soil and marginal hill land of North China, where it is used for food, fuel, and fodder and provides something like one-seventh of the food energy available in the area. ■The sweet potato, growing in sandy soil and providing more food energy per unit of land than other crops, became the main food of the poor in much of the South China rice area. ■

14. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.

Drag your answer choices to the spaces where they belong. To remove an answer choice, click on it.

To review the passage, click VIEW TEXT.

Over the centuries, China has experienced an extraordinary increase in its population.

Answer Choices

A. Understanding the exceptional increase in population in China requires giving up commonly held assumptions relative to the phenomenon of population growth.

B. The economist Dwight Perkins applied a particular statistical method to determine the increase in China’s population.

C. The sudden population growth in China started in its northern and southern provinces, and it spread rapidly to the central and western areas of the country.

D. Improved transportation management and enhanced disease control contributed to China’s population explosion.

E. The increase in China’s food supply, which a ffected population growth, was the result of technological developments in agriculture and capital investment.

F. A steady increase in foreign trade since the 1400s provided the conditions necessary for large-scale agricultural development.

Termite Ingenuity

Termites, social insects which live in colonies that, in some species, contain 2 million individuals or more, are often incorrectly referred to as white ants. But they are certainly not ants. Termites, unlike ants, have gradual metarnorphosis with only three life stage: egg, nymph, and adult. Ants and the other social members of their order, certain bees and wasps, have complete metarnorphosis in four life stages; egg, larva, pupa, and adult. The worker and soldier castes of social ants, bees, and wasps consist of only females, all daughters of a single queen that mated soon after she matured and thereafter never mated again. The worker and soldier castes of termites consist of both males and females, and the queen lives permanently with a male consort.

Since termites are small and soft-bodied, they easily become desiccated and must live in moist places with a high relative humidity. They do best when the relative humidity in their nest is above 96 percent and the temperature is fairly high, an optimum o f about 79°F for temperate zone species and about 86°F for tropical species. Subterranean termites, the destructive species that occurs commonly throughout the eastern United States, attain these conditions by nesting in moist soil that is in contact with wood, their only food. The surrounding soil keeps the nest moist and tends to keep the temperature at a more or less favorable level.

When it is cold in winter, subterranean termites move to burrows below the frost line.

Some tropical termites are more ingenious engineers, constructing huge

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以下，是这次环球托福为正在进行托福备考的考友们整理了托福TPO24阅读真题及答案Lake Breathing During Sleep 。我们建议考友们，先做真题，后看答案进行验证自己的正确率。之后，环球托福还会进一步推出托福TPO24阅读真题的做题思路讲解分析，做完真题后，更便于提高托福阅读能力。 托福TPO24阅读真题Breathing During Sleep Breathing During Sleep Of all the physiological differences in human sleep compared with wakefulness that have been discovered in the last decade, changes in respiratory control are most dramatic. Not only are there differences in the level of the functioning of respiratory systems, there are even changes in how they function. Movements of the rib cage for breathing are reduced during sleep, making the contractions of the diaphragm more important. Yet because of the physics of lying down, the stomach applies weight against the diaphragm and makes it more difficult for the diaphragm to do its job. However, there are many other changes that affect respiration when asleep. During wakefulness, breathing is controlled by two interacting systems. The first is an automatic, metabolic system whose control is centered in the brain stem. It subconsciously adjusts breathing rate and depth in order to regulate the levels of carbon dioxide (CO2) and oxygen (O2), and the acid-base ratio in the blood. The second system is the voluntary, behavioral system. Its control center is based in the forebrain, and it regulates breathing for use in speech, singing, sighing, and so on. It is capable of ignoring or overriding the automatic, metabolic system and produces an irregular pattern of breathing. During NREM (the phase of sleep in which there is no rapid eye movement) breathing becomes deeper and more regular, but there is also a decrease in the breathing rate, resulting in less air being exchanged overall. This occurs because during NREM sleep the automatic, metabolic system has exclusive control over breathing and the body uses less oxygen and produces less carbon dioxide. Also, during sleep the automatic metabolic system is less responsive to carbon dioxide levels and oxygen levels in the blood. Two things result from these changes in breathing control that occur during sleep. First, there may be a brief cessation or reduction of breathing when falling asleep as the sleeper waxes and wanes between sleep and wakefulness and their differing control mechanisms. Second, once sleep is fully obtained, there is an increase of carbon dioxide and a decrease of oxygen in the blood that persists during NREM. But that is not all that changes. During all phases of sleep, several changes in the air passages have been observed. It takes twice as much effort to breathe during sleep because of greater resistance to airflow in the airways and changes in the efficiency of the muscles used for breathing. Some of the muscles that help keep the upper airway open when breathing tend to become more relaxed during sleep, especially during REM (the phase of sleep in which there is rapid eye movement).