考研英语词汇精讲配套讲义(2)(考研英语词汇大纲)

考研英语词汇精讲配套讲义（2）生态、环境类?
?
?
text?one?
few creations of big technology capture the imagination like giant dams. perhaps it is humankinds long suffering at the mercy of flood and drought that makes the ideal of forcing the waters to do our bidding so fascinating. but to be fascinated is also, sometimes, to be blind. several giant dam projects threaten to do more harm than good.
???the lesson from dams is that big is not always beautiful. it doesns bid for first world status includes the giant ataturk?dam.
???but big dams tend not to work as intended. the aswan dam, for example, stopped the nile flooding but deprived egypt of the fertile silt that floods left — all in return for a giant reservoir of disease, which is now so full of silt that it barely generates electricity.
and yet, the myth of controlling the waters persists. this week, in the heart of civilized europe, slovaks and hungarians stopped just short of sending in the troops in their contention over a dam on the danube. the huge complex will probably have all the usual problems of big dams. but slovakia is bidding for independence from the czechs, and now needs a dam to prove itself.
meanwhile, in india, the world bank has given the go-ahead to the even more wrong-headed narmada dam. and the bank has done this even though its advisors say the dam will cause hardship for the powerless and environmental destruction. the benefits are for the powerful, but they are far from guaranteed.
proper, scientific study of the impacts of dams and of the cost and benefits of controlling water can help to resolve these conflicts. hydroelectric power and flood control and irrigation are possible without building monster dams. but when you are dealing with myths, it is hard to be either proper, or scientific. it is time that the world learned the lessons of aswan. you dont need a dam to be saved.
?
?
?
?
?
?
?
?
?
?
?
?
?
???exercises?
?
task 1：quiz at class
?
?
task 2：choose the most suitable answer for each question and then listen to explanations.
?
?
51.?the third sentence of paragraph 1?implies?that? .
[a]?people would be happy if they shut their eyes to?reality
[b]?the blind could be happier than the?sighted
[c]?overexcited people tend to neglect vital?things.
[d]?fascination makes people lose their?eyesight
?
52.?in paragraph 5, “the powerless” probably?refers?to? .
[a] areas short?of?electricity [b] dams without power?stations
[c] poor countries?around?india [d] common people in the narmada dam?area
?
53.?what is the myth concerning giant?dams?
[a] they bring in more?fertile?soil. [b] they help defend the?country.
[c] they strengthen?international?ties. [d] they have universal control of the?waters.
?
54.?what the author tries to suggest may best be?interpreted as? .
[a] “its no use crying over?spilt milk” [b] “more haste, less?speed”
[c] “look before?you?leap” [d] “he who laughs last laughs?best”
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
??text?two?
scattered around the globe are more than 100 small regions of isolated volcanic activity known to geologists as hot spots. unlike most of the world on the contrary, many of them lie deep in the interior of a plate. most of the hot spots move only slowly, and in some cases the movement of the plates past them has left trails of dead volcanoes. the hot spots and their volcanic trails are milestones that mark the passage of the?plates.
???that the plates are moving is now beyond dispute. africa and south america, for example, are moving away from each other as new material is injected into the sea floor between them. the complementary coastlines and certain geological features that seem to span the ocean are reminders of where the two continents were once joined. the relative motion of the plates carrying these continents has been constructed in detail, but the motion of one plate with respect to another cannot readily be translated into motion with respect to the earths interior. it is not possible to determine whether both continents are moving in opposite directions or whether one continent is stationary and the other is drifting away from it. hot spots, anchored in the deeper layers of the earth, provide the measuring instruments needed to resolve the question. from an analysis of the hot-spot population it appears that the african plate is stationary and that it has not moved during the past 30 million years.
???the significance of hot spots is not confined to their role as a frame of reference. it now appears that they also have an important influence on the geophysical processes that propel the plates across the globe. when a continental plate come to rest over a hot spot, the material rising from deeper layer creates a broad dome. as the dome grows, it develops seed fissures (cracks); in at least a few cases the continent may break entirely along some of these fissures, so that the hot spot initiates the formation of a new ocean. thus just as earlier theories have explained the mobility of the continents, so hot spots may explain their mutability ( inconstancy ).
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?exercises?
?
task 1：quiz at class
?
?
task 2：choose the most suitable answer for each question and then listen to explanations.
?
67.?the author?believes?that? .
[a]?the motion of the plates corresponds to that of the earths?interior
[b]?the geological theory about drifting plates has been proved to be?true
[c]?the hot spots and the plates move slowly in opposite?directions
[d]?the movement of hot spots proves the continents are moving?apart
?
68.?that africa and south america were once joined can be deduced from the?fact?that? .
[a]?the two continents are still moving in opposite?directions
[b]?they have been found to share certain geological?features
[c]?the african plates has been stable for 30 million?years
[d]?over 100 hot spots are scattered all around the?globe
?
69.?the hot spot theory may prove useful?in explaining? .
[a]?the structure of the african?plates
[b]?the revival of dead?volcanoes
[c]?the mobility of the?continents
[d]?the formation of new?oceans
?
70.?the passage is mainly?about? .
[a]?the features of volcanic?activities
[b]?the importance of the theory about drifting?plates
[c]?the significance of hot spots in geophysical?studies
[d]?the process of the formation of?volcanoes
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
??text?three?
? emerging from the 1980 census is the picture of a nation developing more and more regional competition, as population growth in the northeast and midwest reaches a near?standstill.
? this?development?—?and?its?strong?implications?for?us?politics?and?economy?in?years?ahead
—?has enthroned the south as americas head?counting.
???altogether, the us population rose in the 1970s by 23.2 million people — numerically the third largest growth ever recorded in a single decade. even so, that gain adds up to only 11.4 percent, lowest in american annual records except for the depression?years.
???americans have been migrating south and west in larger number since world war ii, and the pattern still prevails.
? three?sun?belt?states?—?florida,?texas?and?california?—?together?had?nearly?10?million?more?people?in?1980?than?a?decade?earlier.?among?large?cities,?san?diego?moved?from?14th?to?8th?and?san antonio from 15th to 10th — with cleveland and washington. dc, dropping out of the?top?10.?not all that shift can be attributed to the movement out of the snow-belt, census officials?say.
nonstop waves of immigrants played a role, too — and so did bigger crops of babies as yesterdays “baby boom” generation reached its child-bearing?years.
moreover, demographers see the continuing shift south and west as joined by a related but newer phenomenon: more and more, americans apparently are looking not just for places with more jobs but with fewer people, too. some instances:
●?regionally, the rocky mountain states reported the most rapid growth rate — 37.1 percent since 1970 in a vast area with only 5 percent of the us?population.
●?among states, nevada and arizona grew fastest of all: 63.5 and 53.1 percent respectively. except for florida and texas, the top 10 in rate of growth is composed of western states with 7.5 million people — about 9 per square?mile.
the flight from over-crowdedness affects the migration from snow-belt to more bearable climates.
nowhere do 1980 census statistics dramatize more the american search for spacious living than in the far west. there, california added 3.7 million to its population in the 1970s, more than any other state.
in that decade, however, large numbers also migrated from california, mostly to other parts of the west. often they chose — and still are choosing — somewhat colder climates such as oregon, idaho and alaska in order to escape smog, crime and other plagues of urbanization in the golden?state.
????as a result, californias growth rate dropped during the 1970s, to 18.5 percent — little more than two thirds the 1960s growth figure and considerably below that of other western states.
?
?
?
?
?
?
?
?
?exercises?
?
task 1：quiz at class
?
?
task 2：choose the most suitable answer for each question and then listen to explanations.
?
?
63.?dsicerned from the perplexing picture of population growth the 1980 census provided, america?in 1970s? .
[a]?enjoyed the lowest net growth of population in?history
[b]?witnessed a southwestern shift of?population
[c]?underwent an unparalleled period of population?growth
[d]?brought to a standstill its pattern of migration since world war?ii
?
64.?the census distinguished itself from previous studies on population movement?in?that? .
[a]?it stresses the climatic influence on population?distribution
[b]?it highlights the contribution of continuous waves of?immigrants
[c]?it reveals the americans new

pursuit of spacious?living
[d]?it elaborates the delayed effects of yesterdays “baby?boom”
?
65.?we can see from the available?statistics that? .
[a]?california was once the most thinly populated area in the whole?us
[b]?the top 10 states in growth rate of population were all located in the?west
[c]?cities with better climates benefited unanimously from?migration
[d]?arizona ranked second of all states in its growth rate of?population
?
66.?the word “demographers” (line 1, paragraph 8) most?probably?means? .
[a]?people in favor of the trend of?democracy
[b]?advocates of migration between?states
[c]?scientists engaged in the study of?population
[d]?conservatives clinging to old patterns of?life
?
?
?
?
?
?
?
?
?
?
?
?
?
??text?four?
being a man has always been dangerous. there are about 105 males born for every 100 females, but this ratio drops to near balance at the age of maturity, and among 70-year-olds there are twice as many women as men. but the great universal of male mortality is being changed. now, boy babies survive almost as well as girls do. this means that, for the first time, there will be an excess of boys in those crucial years when they are searching for a mate. more important, another chance for natural selection has been removed. fifty years ago, the chance of a baby (particularly a boy baby) surviving depended on its weight. a kilogram too light or too heavy meant almost certain death. today it makes almost no difference. since much of the variation is due to genes, one more agent of evolution has?gone.
there is another way to commit evolutionary suicide: stay alive, but have fewer children. few people are as fertile as in the past. except in some religious communities, very few women have 15 children. nowadays the number of births, like the age of death, has become average. most of us have roughly the same number of offspring. again, differences between people and the opportunity for natural selection to take advantage of it have diminished. india shows what is happening. the country offers wealth for a few in the great cities and poverty for the remaining tribal peoples. the grand mediocrity of today — everyone being the same in survival and number of offspring — means that natural selection has lost 80% of its power in upper-middle class india compared to the?tribes.
for us, this means that evolution is over; the biological utopia has arrived. strangely, it has involved little physical change. no other species fills so many places in nature. but in the past 100,000 years — even the past 100 years — our lives have been transformed but our bodies have not. we did not evolve, because machines and society did it for us. darwin had a phrase to describe those ignorant of evolution: they “look at an organic being as a savage looks at a ship, as at something wholly beyond his comprehension.” no doubt we will remember a 20th century way of life beyond comprehension for its ugliness. but however amazed our descendants may be at how far from utopia we were, they will look just like?us.
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?exercises?
?
task 1：quiz at class
?
?
task 2：choose the most suitable answer for each question and then listen to explanations.
?
55.?what used to be the danger in being a man according to the first?paragraph?
［a］a lack?of?mates. ［b］a fierce?competition.
［c］a lower?survival rate. ［d］a defective?gene.
?
56.?what does the example of india?illustrate?
［a］wealthy people tend to have fewer children than poor people.
［b］natural selection hardly works among the rich and the poor.
［c］the middle class population is 80% smaller than that of the tribes.
［d］india is one of the countries with a very high birth rate.
?
57.?the author argues that our bodies have stopped?evolving because? .
［a］life has been improved by technological advance
［b］the number of female babies has been declining
［c］our species has reached the highest stage of evolution
［d］the difference between wealth and poverty is disappearing
?
58.?which of the following would be the best title for the?passage?
［a］sex ratio changes in human evolution
［b］ways of continuing mans evolution
［c］the evolutionary future of?nature
［d］human evolution going?nowhere