Theauthortellsusinparagraph4________.

We can begin our discussion of “population as global issue” with what most persons mean when they discuss “the population problem”: too many people on earth and a too rapid increase in the number added each year. The facts are not in dispute, It was quite right to employ the analogy that likened demographic growth to “a long, thin powder fuse that burns steadily and haltingly until it finally reaches the charge and explodes.”

To understand the current situation, which is characterized by rapid increases in population, it is necessary to understand the history of population trends. Rapid growth is a comparatively recent phenomenon. Looking back at the 8,000 years of demographic history, we find that populations have been virtually stable or growing very slightly for most of human history. For most of our ancestors, life was hard, often nasty, and very short. There was high fertility in most places, but this was usually balanced by high mortality. For most of human history, it was seldom the case that one in ten persons would live past forty, while infancy and childhood were especially risky periods. Often, societies were in clear danger of extinction because death rates could exceed their birthrates. Thus, the population problem throughout most of history was how to prevent extinction of the human race.

This pattern is important to notice. Not only does it put the current problems of demographic growth into a historical perspective, but it suggests that the cause of rapid increase in population in recent years is not a sudden enthusiasm for more children, but an improvement in the conditions that traditionally have caused high mortality.

Demographic history can be divided into two major periods: a time of long, slow growth which extended from about 8,000 BC.till approximately AD. 1650. In the first period of some 9600 years, the population increased from some 8 million to 500 million in 1650. Between 1650 and the present, the population has increased from 500 million to more than 4 billion. And it is estimated that by the year 2000 there will be 6.2 billion people throughout the world. One way to appreciate this dramatic difference in such abstract numbers is to reduce the time frame to something that is more manageable. Between 8000BC and 1650, an average of only 50,000 persons was being added annually to the world’s population each year. At present, this number is added every six hours. The increase is about 80,000,000 persons annually.

1.Which of the following demographic growth pattern is most suitable for the long thin powder fuse analogy?

A.A virtually stable or slightly decreasing period and then a sudden explosion of population.

B.A slow growth for a long time and then a period of rapid, dramatic increase.

C.Too many people on earth and a few rapid increase in the number added each year.

D.A long period when death rates exceeds birthrates and then a short period with higher fertility and lower mortality.

2.During the first period of demographic history, societies were often in danger of extinction because___.

A.only one in ten persons could live past 40.

B.there was higher mortality than fertility in most places.

C.it was too dangerous to have babies due to the poor conditions.

D.our ancestors had little enthusiasm for more children.

3.Which statement is true about population increase?

A.There might be an increase of 2.2 billion persons from now to the year 2000.

B.About 50,000 babies are born every six hours at present.

C.Between 8000 BC and the present, the population increase is about 80,000,000 persons each year.

D.The population increased faster between 8000BC and 1650 than between 1650 and the present.

4.The author of the passage intends to___.

A.warn people against the population explosion in the near future.

B.compare the demographic growth pattern in the past with that after 1650.

C.find out the cause for rapid increase in population in recent years.

D.present us a clear and complete picture of the demographic growth.

5.The word “demographic” in the first paragraph means___.

A.statistics of human.

B.surroundings study.

C.accumulation of human.

D.development of human.

ThediscoveryoftheAntarcticnotonlyprovedoneofthemostinterestingofallgeographicaladventures,butcreatedwhatmightbecalled“theheroicageofAntarcticexploration”.Bytheirtremendousheroism,mensuchasShakleton,Scott,andAmundsencausedanewcontinenttoemergefromtheshadows,andyetthatheroicage,littlemorethanacenturyold,isalreadypassing.Modernscienceandinventionsarerevolutionizingtheendurance,futurejourneysintotheseicywasteswillprobablydependonmotorvehiclesequippedwithcaterpillartractionratherthanonthedogsthatearlierdiscoverersfoundsoinvaluableandhardlycomparable.

FewrealizethatthisAntarcticcontinentisalmostequalinsizetoSouthAmerica,andenormousfieldofworkawaitsgeographersandprospectors.Thecoastsofthiscontinentremaintobeaccuratelycharted,andthemapingofthewholeoftheinteriorpresentsaformidabletasktothecartographerswhoundertakethework.Oncetheirlaborsarecompleted,itwillbepossibletoprospectthevastnaturalresourceswhichscientistsbelievewillfurnishoneofthelargesttreasurehoardsofmetalsandmineralstheworldhasyetknown,andalmostinexhaustiblesourcesofcopper,coal,uranium,andmanyotheroreswillbecomeavailabletoman.SuchdiscoverieswillusherinaneraofpracticalexploitationoftheAntarcticwastes.

Thepolardarknesswhichhidesthiscontinentforthesixwintermonthswillbedefeatedbyhugebatteriesoflight,andmakepossibletheestablishingofair-fieldsforthefutureinter-continentalairservicesbymakingtheseareasaslightasday.Presentflyingrouteswillbecompletelychanged,fortheAntarcticrefuelingbaseswillmakeflightsfromAustraliatoSouthAmericacomparativelyeasyoverthe5,000milesjourney.

Theclimateisnotlikelytoofferaninsuperableproblem,fortheexplorerAdmiralByrdhasshownthattheclimateispossibleevenformencompletelyuntrainedforexpeditionsintothosefrozenwastes.Someofhispartiesweremenwhohadneverseensnowbefore,andyetherecordsthattheysurvivedtherigorsoftheAntarcticclimatecomfortably,sothat,providedthattheappropriateinstallationsaremade,wemayassumethathumanbeingsfromallcountriescouldlivetheresafely.Byrdevenaffirmsthatitisprobablythemosthealthyclimateintheworld,fortheintensecoldofthousandsofyearshassterilizethiscontinent,andrendereditabsolutelygermfree,withtheconsequencesthatordinaryandextraordinarysicknessanddiseasesfromwhichmansuffersinotherzoneswithdifferentclimatesarehereutterlyunknown.Thereexistnoproblemsofconservationandpreservationoffoodsupplies,forthelatterkeepindefinitelywithoutanysignsofdeterioration;itmayevenbethatlatergenerationswillcometoregardtheAntarcticasthenaturalstorehouseforthewholeworld.

Plansarealreadyonfoottosetuppermanentbasesontheshoresofthiscontinent,andwhatsofewyearsagowasregardedasa“deadcontinent”nowpromisestobeamostactivecenterofhumanlifeandendeavor.

1.WhendidmanbegintoexploretheAntarctic?

A.About100yearsago.

B.Inthiscentury.

C.Atthebeginningofthe19thcentury.

D.In1798.

2.Whatmusttheexplorersbe,eventhoughtheyhavemodernequipmentandtechniques?

A.Braveandtough

B.Stubbornandarrogant.

C.Well-likedandhumorous.

D.Stoutandsmart.

3.Themosthealthyclimateintheworldis___.

A.inSouthAmerica.

B.intheArcticRegion.

C.intheAntarcticContinent.

D.intheAtlanticOcean.

4.WhatkindofmetalsandmineralscanwefindintheAntarctic?

A.Magnetite,coalandores.

B.Copper,coalanduranium.

C.Silver,naturalgasanduranium.

D.Aluminum,copperandnaturalgas.

5.Whatisplannedforthecontinent?

A.Buildingdamsalongthecoasts.

B.Settingupseveralsummerresortsalongthecoasts.

C.Mappingthecoastandwholeterritory.

D.Settinguppermanentbasesonthecoasts.

Part III Cloze

Directions: There are twenty blanks in the following passage. For each blank there are four choices. Choose the one that best fits into the passage and then marks your answer on the Answer Sheet.

What makes a child speak a language has long been a puzzle to linguists. 61 speaking, there are two schools of linguists, both of whom try to explain 62 a child picks up a language so easily. The fact that a child picks a language 63 is 64 : At one year old, a child is able to say “bye-bye”; at two, he is able to use fifty; by there he begins to 65 tenses. The famous American linguist Noam Chomsky 66 that human being have a sort of built-in system for language use, and that the 67 is 68 . Children are not taught language 69 they are taught arithmetic. Other linguists, 70 , hold the view that a child learns 71 of his language from the hints in the environment. 72 , theorists of both schools 73 that there is a biological basis for language use. The 74 is which is more important, the inner ability or the environment. This is certainly a field 75 to be explored. Researchers from both schools are busy finding evidence to 76 their own theory, but 77 side is persuading the other.

It seems that in order to 78 why a child learns a language so easily, we have to 79 the joint efforts of both schools. Some linguist, like De Villiers, has recognized the value of cooperation, and 80 linguists of both sides to work together.

61. A. Surprisingly B. Personally C. Properly D. Roughly

62. A. that B. when C. why D. how

63. A. independently B. naturally C. without help D. with ease

64. A. confusing B. surprising C. questioned D. suspected

65. A. master B. study C. have D. get

66. A. doubts B. believes C. realizes D. criticizes

67. A. help B. teacher C. environment D. hint

68. A. quite essential B. very important C. not necessary D. only secondary

69. A. as B. for C. when D. though

70. A. in particular B. as a result C. however D. therefore

71. A. a little B. some C. nothing D. most

72. A. Before B. From now on C. Just now D. By now

73. A. suspect B. disagree C. agree D. realize

74. A. case B. argument C. problem D. question

75. A. waiting B. planning C. never D. unlikely

76. A. provide B. create C. supply D. support

77. A. not a B. one C. neither D. either

78. A. find out B. rule out C. search for D. look for

79. A. get rid of B. trust in C. rely on D. persist in

80. A. ordered B. criticized C. challenged D. urged

Whileintegrasedeletesanimmunecell'sgeneticmaterialandreplacesitwithitsown,itactslike________inawordprocessor.