托福阅读真题第17套

Determining the Ages of the Planets and the Universe

Paragraph1

The planets of our solar system all revolve around the Sun in the same direction and in orbits that lie in nearly the same plane.This is strong evidence that the planets formed simultaneously from a single disk of material that rotated in the same direction as the modern planets.

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Precisely when the planets came into being has been a difficult issue to resolve.While Earth’s water is necessary for life,its abundance near the planet’s surface makes rapid erosion inevitable.Continuous alteration of the crust by erosion and also by igneous (volcanic)and metamorphic(pressure and heat within Earth)processes makes unlikely any discovery of rocks nearly as old as Earth.Thus geologists have had to look beyond this planet in their efforts to date Earth’s origin.Fortunately,we do have samples of rock that appear to represent the primitive material of the solar system. These samples are meteorites,which originate as extraterrestrial objects,called meteors,that have been captured in Earth’s gravitational field and have then crashed into our planet.

1.According to paragraphs1and2,what evidence leads astronomers to believe that

all the planets formed at approximately the same time?

Samples of rocks from all the planets are the same age.

All the planets orbit the Sun in the same direction and in about the same plane.

All planets have the same igneous and metamorphic processes.

The gravitational field of each planet is about the same strength. Paragraphs1and2are marked with arrows[→]

2.The word”inevitable”in the passage is closet in meaning to

continuous

obvious

certain

easy

3.Which of the following is NOT mentioned in paragraph2as a cause of constant

change to Earth’s crust?

Water

Igneous processes

Metamorphic processes

Meteorites

Paragraph2is marked with an arrow[→]Paragraph3

Some meteorites consist of rocky material and,accordingly,are called stony meteorites.Others are metallic and have been designated iron meteorites even though they contain lesser amounts of elements other than iron.Still others consist of mixtures of rocky and metallic material and thus are called stony-iron meteorites. Meteors come in all sizes,from small particles to the small planets known as asteroids; no asteroid,however,has struck Earth during recorded human history.Many meteorites appear to be fragments of larger bodies that have undergone collisions and broken into pieces.Iron meteorites are fragments of the interiors of these bodies, comparable to Earth’s core,and stony meteorites are from outer portions of these bodies,comparable to Earth’s mantle(the layer between the core and outer crust).

4.The word”accordingly”in the passage is closet in meaning to

correspondingly

frequently

interestingly

informally

5.Which of the following can be inferred from paragraph3about meteorites?

Their composition can help determine the part of the larger body from which they broke off.

They are difficult to distinguish from rocks in Earth’s mantle.

Their collisions with Earth have become more frequent than in the past.

They are older than the rest of the solar system.

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6.According to paragraph3,which of the following is a characteristic of asteroids? They are the largest meteors.

They are made mostly of iron and other metals.

They often collide with Earth.

They are the oldest meteors.

Paragraph3is marked with an arrow[→]

Paragraph4

Meteorites have been radiometrically dated by means of several decay systems, including rubidium-strontium,potassium-argon,and uranium-thorium.The dates thus derived tend to cluster around4.6billion years,which suggests that this is the approximate age of the solar system.After many meteorites had been dated,it was gratifying to find that the oldest ages obtained for rocks gathered on the surface of the Moon also were approximately4.6billion years.This must,indeed,be the age of the solar system.Ancient rocks can be found on the Moon because the lunar surface, unlike that of Earth,has no water to weather and erode rocks and is characterized by only weak movements of its crust.7.Which of the following can be inferred from paragraph4about the radiometric

dating of meteorites?

Scientists tried several different radiometric systems before finding one that worked.

The radiometric dating of different meteorites produced similar results.

Many meteorites were damaged by the radiometric dating.

Radiometric dating was not as accurate as scientists expected.

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8.The word”cluster”in the passage is closet in meaning to

approach

spread

group

vary

9.According to paragraph4,why are scientists confident that the age of the oldest

meteorites they studied is also the age of the solar system?

Radiometric dating has been proven to be reliable.

The oldest rocks found on the surface of the Moon are the same age as the meteorites.

No meteorites have been found that are younger than4.6billion years old.

Meteorites on the Moon are the same age as those on other planets. Paragraph4is marked with an arrow[→]

Paragraph5

Determining the age of the universe has been more complicated.Most stars in the universe are clustered into enormous disk-like galaxies.The distance between our galaxy,known as the Milky Way,and all others is increasing.In fact,all galaxies are moving away from one another,evidence that the universe is expanding.It is not the galaxies themselves that are expanding but the space between them.What is happening is analogous to inflating a balloon with small coins attached to its surface. The coins behave like galaxies:although they do not expand,the space between them does.Before the galaxies formed,matter that they contain was concentrated with infinite density at a single point from which it exploded in an event called the big bang.Even after it assembled into galaxies,matter continued to spread in all directions from the site of the big bang.

10.The word”enormous”in the passage is closet in meaning to

expanding

very bright

distant

huge

11.Why does the author refer to“inflating a balloon with small coins attached to itssurface”?

To help explain how the universe can expand while the galaxies remain the same size

To imply that the universe must eventually stop expanding

To support the statement that most stars are found in disk-shaped galaxies

To help explain how the universe began as a single point of dense matter

Paragraph6

The evidence that the universe is expanding makes it possible to estimate its age.This evidence,called the redshift,is an increase in the wavelengths of light waves traveling through space—a shift toward the red end of the visible spectrum of wavelengths. Expansion of the space between galaxies causes this shift by stretching light waves as they pass through it.The farther these light waves have traveled through space,the greater the redshift they have undergone.For this reason,light waves that reach Earth from distant galaxies have larger redshifts than those from nearby galaxies. Calculations based on these redshifts indicate that about13.7billion years ago all of the galaxies would have been at one spot,the site of the big bang.This,then,is the approximate date of the big bang and the age of the universe.

12.According to paragraph6,how did astronomers learn that the universe is

expanding?

By measuring the distance between galaxies

By observing the movement of stars within galaxies

By studying the wavelengths of light from distant galaxies

By comparing the sizes of different galaxies

Paragraph6is marked with an arrow[→]

Paragraph3

■Some meteorites consist of rocky material and,accordingly,are called stony meteorites.■Others are metallic and have been designated iron meteorites even though they contain lesser amounts of elements other than iron.■Still others consist of mixtures of rocky and metallic material and thus are called stony-iron meteorites.■Meteors come in all sizes,from small particles to the small planets known as asteroids;no asteroid,however,has struck Earth during recorded human history. Many meteorites appear to be fragments of larger bodies that have undergone collisions and broken into pieces.Iron meteorites are fragments of the interiors of these bodies,comparable to Earth’s core,and stony meteorites are from outer portions of these bodies,comparable to Earth’s mantle(the layer between the core and outer crust).

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

added to the passage.

Several varieties of meteorites have been observed.Where would the sentence best fit?Click on a square[■]to add the sentence to the passage.

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 answer choices 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 worth2points.

Drag your choices to the spaces where they belong.To review the passage,click on

View Text.

Answer Choices

A.Determining the age of the planets by examining rocks on Earth is difficult because Earth’s crust is constantly changing.

B.Meteorites found on Earth and rocks from the Moon’s surface are the best evidence for estimating the age of the planets.

C.The expansion of the universe makes it possible to estimate its age by measuring the amount of the redshift of light coming from distant galaxies.

D.All three kinds of meteorites are similar in composition to Earth in that they have an inner core,a rocky mantle,and an outer crust.

E.Radiometric dating of meteorites recovered from the Moon shows that they are older than those that are found on Earth.

F.The redshift phenomenon measures the rate at which the stars in a galaxy are moving away from each other.

Costs and Benefits of Dispersal（17年上半年再次考过）

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In order to move from one home base to another,animals must expend calories not only while moving but even before the dispersal when they invest in the development of the muscles needed to move.For example,if a cricket is to leave a deteriorating environment and move to a new and better place,it will need large flight muscles to fly away.Presumably,the calories and materials that go into flight muscle development and maintenance have to come out of the general energy budget of the animal.This means that other organ systems cannot develop as rapidly as they could otherwise,which may mean that the flight-capable individual is,in some other respects,less fit to survive.1.The word”Presumably”in the passage is closet in meaning to

It is reasonable to assume

It is possible

It can be argued

It is certainly true

2.In paragraph1,the discussion of cricket dispersal is used to illustrate which of the

following principles?

For dispersing animals,the benefits of dispersal exceed the costs.

Dispersal always involves costs for the dispersing animal.

Only animals with the greatest fitness for survival are able to disperse.

Dispersal,as much as organ development,requires energy.

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Paragraph2

Dispersing individuals not only have to pay energetic,developmental,and travel costs but are also more often exposed to predators—all of which raises the question,why are animals so often willing to leave home even when this means leaving a familiar, resource-rich location?This question is particularly pertinent for species in which some individuals disperse while others do not or do not disperse as far.One species in which some individuals travel farther than others is Belding’s ground squirrel.Young male squirrels travel about150meters from the burrow in which they were born, whereas young females usually settle down only50meters or so from where they were born.Why should young Belding’s ground squirrels disperse at all,and why should the males disperse farther than their sisters?

3.The word”pertinent”in the passage is closet in meaning to

puzzling

important

complex

relevant

4.According to paragraph2,what is of particular interest about the dispersal of

Belding’s ground squirrels?

Young squirrels disperse farther than adults.

Young squirrels disperse even from resource-rich areas.

The males and females have different patterns of dispersal.

They leave the mother’s burrow at an earlier age than other squirrels. Paragraph2is marked with an arrow[→]

5.It can be inferred from paragraph2that the phenomenon of dispersal

is difficult to observe in the wild

occurs for reasons that are not always immediately apparent

is motivated by the desire to obtain more or better resources

has few benefits for most species

Paragraph2is marked with an arrow[→]

Paragraph3

According to one argument,dispersal by juvenile animals of many species may be an adaptation against problems associated with inbreeding.When two closely related individuals mate,their offspring are more likely to manifest genetic diseases than are the offspring of genetically unrelated individuals,and as a result,inbreeding tends to produce animals that are less likely to survive to adulthood and reproduce.Dispersal of juveniles makes inbreeding less likely.

6.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.

When closely related individuals mate,their offspring are likely to manifest genetic diseases that will probably be passed on to the next generation.

Genetic diseases inherited from parents that are not related make it less likely that the affected offspring will survive to adulthood and reproduce.

When two related individuals mate,their offspring may survive to adulthood,but they are unlikely to reproduce.

There is a tendency for the offspring of closely related parents to have genetic diseases that make it less likely they will survive and reproduce.

Paragraph4

If avoidance of inbreeding is the point of dispersing,then one might expect as many female ground squirrels as males to travel150meters from their natal burrow.In fact females do not disperse as far as males,perhaps because the costs and benefits of dispersal differ for the two sexes.It has been suggested that the reproductive success of female Belding’s ground squirrels depends on their possession of a territory in which to rear their young.Female ground squirrels that remain near their birthplace enjoy assistance from their mothers in the defense of their burrows against rival females.Thus,the benefits of remaining on familiar ground are greater for females than for males.

7.According to paragraph4,young female Belding’s ground squirrels may remain

closer to where they were born than do males in order to

avoid inbreeding with their male siblings

avoid competition with other females for territory

save energy they need to defend their burrows

benefit from their mothers’help

Paragraph4is marked with an arrow[→]

Paragraph5There may,however,be another reason why male mammals disperse greater distances than females.The usual rule is that males,not females,fight with one another for access to mates,and,therefore,males that lose such conflicts may find it advantageous to move away from same-sex rivals that they cannot subdue.Although this hypothesis probably does not apply to Belding’s ground squirrels,since young males have not been seen fighting with older ones around the time of dispersal,the idea is more plausible with respect to some other species,such as lions.

8.According to paragraph5,the hypothesis that males disperse as a result of

conflicts with other males is not supported in the case of Belding’s ground squirrels because

young male squirrels that lose fights to other males do not disperse

unlike most species,it is the females,not the males,that fight with each other

there is no evidence that young male squirrels fight with other males before dispersing

fights between males generally take place after the males have dispersed Paragraph5is marked with an arrow[→]

9.The word”subdue”in the passage is closet in meaning to

remove

fight

defeat

accept

Paragraph5

There may,however,be another reason why male mammals disperse greater distances than females.The usual rule is that males,not females,fight with one another for access to mates,and,therefore,males that lose such conflicts may find it advantageous to move away from same-sex rivals that they cannot subdue.Although this hypothesis probably does not apply to Belding’s ground squirrels,since young males have not been seen fighting with older ones around the time of dispersal,the idea is more plausible with respect to some other species,such as lions. Paragraph6

Lions live in large groups,or prides,from which young males disperse.In contrast, the daughters of the resident lionesses usually spend their entire lives close to where they were born.The sedentary females benefit from their familiarity with good hunting grounds and safe breeding dens in their natal territory,among other things. The departure of many young male lions coincides with the arrival of new mature males that violently displace the previous masters of the pride and chase off the males that are not yet adults in the pride as well.These observations support the mate-competition hypothesis for male dispersal.However,if young males are not evicted after a pride takeover,they often leave anyway without any coercion from adult males and without ever having attempted to mate with their female relatives.Moreover,mature males that have claimed a pride sometimes disperse again, expanding their range to add a second pride of females,at a time when their daughters in the first pride are becoming sexually mature.Inhibitions against inbreeding apparently exist in lions and cause males to leave home.

10.According to paragraphs5and6,the patterns of dispersal in Belding’s ground

squirrels and lions are similar in which of the following ways?

Young males are forced to disperse by older males.

Avoiding inbreeding is probably not a factor in the explanation of the pattern of dispersal.

Males disperse when new siblings are born.

The males disperse farther than the females.

Paragraphs5and6are marked with arrows[→]

11.The phrase”coincides with”in the passage is closet in meaning to

is driven by

occurs at the same time as

makes possible

is a sign of

12.Why does the author provide the information that“if young males are not evicted

after a pride takeover,they often leave anyway without any coercion from adult males and without ever having attempted to mate with their female relatives”?

To support the conclusion that made lions disperse to find mates to which they are not closely related

To indicate that the mate-competition hypothesis does not fully account for the dispersal of young male lions

To imply that young male lions voluntarily leave a pride that has been taken over because the adult males prevent them from mating within the pride

To indicate that males,not females,leave a pride after it has been taken over by adult males

Paragraph4

■If avoidance of inbreeding is the point of dispersing,then one might expect as many female ground squirrels as males to travel150meters from their natal burrow.■In fact females do not disperse as far as males,perhaps because the costs and benefits of dispersal differ for the two sexes.■It has been suggested that the reproductive success of female Belding’s ground squirrels depends on their possession of a territory in which to rear their young.■Female ground squirrels that remain near their birthplace enjoy assistance from their mothers in the defense of their burrows against rival females.Thus,the benefits of remaining on familiar ground are greater for females than for males.

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

However,inbreeding can be avoided without both males and their female relatives dispersing the same distance.

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

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 answer choices 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 worth2points.

Drag your choices to the spaces where they belong.To review the passage,click on

View Text.

Answer Choices

A.There are a number of competing explanations of why animals disperse,but none of them is consistent with all the observed patterns of dispersal.

B.The reason there is little inbreeding among lions is that young males are driven away from their female relatives by the adult males who forcibly take over a lion pride.

C.Inbreeding significantly lowers the likelihood that offspring will survive,and so avoiding inbreeding is a significant benefit of dispersal.

D.Since males of most species must establish a territory for mating,dispersing of the males makes it more likely that most males will be able to reproduce.

E.There need to be significant benefits for a species to disperse because the requirements of dispersal involve energy costs and dangers for the dispersing individuals.

F.In mammal species,young males often leave their family group while related females benefit from remaining in close association with each other and their birthplace.

The Multiplier Effect

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The causes behind the rapid development of the Minoan and Mycenaean civilizations in the Aegean during the late third and second millennia B.C.E.have intrigued scholars for years.Until recently,most explanations attributed Aegean development tooutside influence.Civilization had emerged in Mesopotamia by3000B.C.E,and, some archeologists argued,Mesopotamian trade introduced civilized ideas and technological innovations into nearby,less advanced areas.Others hypothesized that civilization was brought to the Aegean by invasion from some adjacent region,of which Anatolia in modern Turkey seemed the most plausible.

1.Paragraph1implies which of the following about traditional scholarship

concerning the development of Aegean civilizations?

It focused on the influence of Aegean trade on more advanced civilization rather than the invasion of the Aegean by a technologically advanced culture.

The development of Minoan civilization was thought to require a different explanation from that for the development of Mycenaean civilization.

It maintained that the rapid development of Aegean civilization could be explained only through external influence.

There was general agreement that Anatolia and Mesopotamia were both responsible for the development of civilization in the Aegean.

Paragraph1is marked with an arrow[→]

Paragraph2

In a work published in1972,Professor Colin Renfrew approached the problem from a different viewpoint.He argued that the scanty available evidence for invasion or immigration from Anatolia into Greece in the early Bronze Age(about3300-2200 B.C.E.)showed that,at most,such incursion was limited,and that it could not be regarded as responsible for the transformation of society there.Trade,though clearly documented,was also an inadequate explanation in itself.To understand the major changes in social organization and complexity that took place,it was necessary,said Renfrew,to determine the impact that new variables emerging in the early Bronze Age may have had on every interrelated aspect of the local social system.The two new major developments he considered were changes in the subsistence economy and the introduction of bronze metallurgy.

2.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.

Renfrew said that local variables affected the complex social organization of the early Bronze Age.

Renfrew said that the major changes in social organization could be understood only by examining the effects of the new developments that took place in the early Bronze Age.

The early Bronze Age,Renfrew said,was a time in which there were major changes to many interrelated aspects of local social systems.

To understand the social organization and complexity of the early Bronze Age,it was necessary,said Renfrew,first to determine what new variables had emerged.Paragraph3

The economy of Neolithic Greece was based on growing grains and raising sheep. Early in the third millennium B.C.E.,cultivation of grape vines and olive trees also became important in southern Greece and the Aegean Islands.Both crops were eminently suitable for trade and storage in the form of olive oil and wine.They were grown on land that was not suitable for grain farming.Their cultivation required work at a different time of year from that needed by grain crops,and much of this work, such as harvesting,was relatively light.As a result,agricultural yields were substantially increased without disrupting established agricultural practice.That increase in turn allowed,or stimulated,population growth.For the first time there was enough demand for specialized crafts and services to justify the existence of full-time craftspeople,who could be supported from the extra agricultural output.

3.The word”justify”in the passage is closet in meaning to

include within the social system

provide a rational basis for

employ

encourage

4.According to paragraph3,growing grape vines and olive trees increased

agricultural yields because

grapes and olives were mostly used for trade rather than for competing with established crops in local markets

grape vines and olive trees could be cultivated on land that was also used for raising sheep

growing grapes and olives did not require the services of specialized workers

grape vines and olive trees did not compete with other crops for land or labor Paragraph3is marked with an arrow[→]

5.According to paragraph3,the increased importance of grape and olive cultivation

led to which of the following changes in Greece?

An increase in the number of inhabitants

An increase in the amount of grain traded

An increase in the percentage of farmers in the population

The development of new methods of storing foods

Paragraph3is marked with an arrow[→]

Paragraph4

Some copper artifacts were made during the fourth millennium B.C.E,but there were not many of them and they had little economic or social significance.When,in the third millennium,copper began to be mixed with tin to produce the relatively hard alloy bronze,demand for metal goods grew.Bronze could be used to make a range of useful new tools and weapons and a variety of impressive ornaments.The demand for metalwork stimulated further specialization in crafts such as toolmaking and jewelry

making.The new tools promoted the development of other crafts,like carpentry and shipbuilding.Competition for prestigious or useful craft products and for control of their producers helped to heighten both social differences within communities and conflicts between them,resulting in the emergence of local chieftains,who were also in many instances warriors.These chieftains regulated agricultural and craft production,operating a distribution system through which the farmers could obtain tools or ornaments they needed or wanted.The organizational demands of controlled distribution made it necessary to develop methods of measurement and recording, which led to the development of writing.

6.The word”promoted”in the passage is closet in meaning to

required

benefited from

encouraged

speeded up

7.According to paragraph4,why did the invention of bronze lead to increased

conflict?

It resulted in more effective weapons for warriors.

It led to competition for the control of skilled craftspeople and their products.

It left the craftspeople who had been involved in making copper products without and occupation.

It led to competition for available supplies of tin to be used in the production of bronze.

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8.All of the following are discussed in paragraph4as changes in Greek society after

bronze was introduced EXCEPT:

Social differentiation within communities increased.

Metalcraft workers became more specialized.

Methods were invented for documenting the distribution of goods.

Craft workers gained greater independence from local chieftains.

Paragraph4is marked with an arrow[→]

Paragraph5

Renfrew argued that any single innovation would have had a limited or negligible effect on social organization because the inherently conservative nature of societies acts to minimize change.However,the interaction of several simultaneous developments created a multiplier effect.In the Aegean,increased agricultural productivity provided the means to support craft specialization,while bronze metallurgy provided the technology for producing highly valued new products.These factors set in motion a series of changes in other subsystems of society.Those changes in turn resulted in what,in a term borrowed from electronics,are called positive feedback loops—alterations in the workings of a social system that serve to reinforcethemselves.Thus Aegean society was transformed from one consisting of basically self-sufficient and egalitarian farming villages to one of prosperous,hierarchical chiefdoms,with palace-dwelling rulers,actively competing with one another both at home and in international trade.

9.The phrase“several simultaneous developments”in the passage is closet in

meaning to

independent developments

developments that reinforced each other

developments that occurred at the same time

developments that followed one another in a sequence

10.The word”hierarchical”in the passage is closet in meaning to

having several levels of authority

dependent on military support

hereditary

nondemocratic

11.What role does the idea of a“multiplier effect”serve in Renfrew’s explanation of

the development of civilization in the Aegean?

It allows him to argue that the combined effect of individual developments can lead to a major transformation of a social organization.

It allows him to explain the idea of a positive feedback loop.

It allows him to explain the inherently conservative nature of societies.

It allows him to explain how the changes in agriculture,bronze metallurgy,and craft specialization came about.

12.According to paragraph5,the transformation of Aegean society involved all the

following EXCEPT

interdependence of the society’s various social and economic structures

economic success

competition between chiefdoms for economic dominance

social and political equality

Paragraph5is marked with an arrow[→]

Paragraph2

In a work published in1972,Professor Colin Renfrew approached the problem from a different viewpoint.■He argued that the scanty available evidence for invasion or immigration from Anatolia into Greece in the early Bronze Age(about3300-2200 B.C.E.)showed that,at most,such incursion was limited,and that it could not be regarded as responsible for the transformation of society there.■Trade,though clearly documented,was also an inadequate explanation in itself.■To understand the major changes in social organization and complexity that took place,it was necessary,said Renfrew,to determine the impact that new variables emerging in the early BronzeAge may have had on every interrelated aspect of the local social system.■The two new major developments he considered were changes in the subsistence economy and the introduction of bronze metallurgy.

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

added to the passage.

Instead,Renfrew emphasized the complex internal dynamics of change.

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

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 answer choices 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 worth2points.

Drag your choices to the spaces where they belong.To review the passage,click on

View Text.

A.The emergence of Aegean civilization was the result of internal factors interacting with each other in a way that multiplied each other’s effects.

B.An increase in population created a shortage of agricultural land that increased social tensions and forced many farmers to become warriors for local chieftains.

C.More effective bronze weapons increased the power of local chieftains,who imposed a system in which they collected farm and craft products in exchange for protecting their subjects.

D.Once people began producing bronze,it surpassed wine and olive oil as the most important good traded in the Aegean.

E.Agricultural surpluses from the production of olive oil and wine and the introduction of bronze technology together supported population growth,the development of crafts,and economic expansion.

F.As the economy diversified and grew,a higher level of social organization was required,a need that encouraged the emergence of chieftains who regulated the distribution of economic goods.参：

Determining the Ages of the Planets and the Universe：BCDAA,ABCBD,ACA,123 Costs and Benefits of Dispersal：ADDCB,DDCCD,BBB,356

The Multiplier Effect：CBBDA,CBDCA,ADC,156