TOEFL全真试题4.docx

TOEFL全真试题4.docx

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TOEFL全真试题4

TOEFL全真试题（4

Time:

55minutes（includingthereadingofthedirections）.Nowsetyourclockfor55minutes.

Question1-12

Orchidsareuniqueinhavingthemosthighlydevelopedofallblossoms,inwhichtheusualmaleandfemalereproductiveorgansarefusedinasinglestructurecalledthecolumn.Thecolumnisdesignedsothatasinglepollinationwillfertilizehundredsofthousands,andinsome

casesmillions,ofseeds,somicroscopicandlighttheyareeasilycarriedbythebreeze.Surroundingthecolumnarethreesepalsandthreepetals,sometimeseasilyrecognizableassuch,oftendistortedintogorgeous,weird,butalwaysfunctionalshapes.Themostnoticeableofthe

petalsiscalledthelabellum,orlip.Itisoftendramaticallymarkedasanunmistakablelanding

striptoattractthespecificinsecttheorchidhaschosenasitspollinator.

Toluretheirpollinatorsfromafar,orchidsuseappropriatelyintriguingshapes,colors,andscents.Atleast50differentaromaticcompoundshavebeenanalyzedintheorchidfamily,eachblendedtoattractone,oratmostafew,speciesofinsectsorbirds.Someorchidsevenchangetheirscentstointerestdifferentinsectsatdifferenttimes.

Oncetherightinsecthasbeenattracted,someorchidspresentallsortsofone-wayobstacle

coursestomakesureitdoesnotleaveuntilpollenhasbeenaccuratelyplacedorremoved.Bysuchingeniousadaptationstospecificpollinators,orchidshaveavoidedthehazardsoframpant

crossbreedinginthewild,assuringthesurvivalofspeciesasdiscreteidentities.Atthesametime

theyhavemadethemselvesirresistibletocollectors.

1.Whatdoesthepassagemainlydiscuss?

（A）Birds

（B）Insects

（C）Flowers

（D）Perfume

2Theorchidisuniquebecauseof

（A）thehabitatinwhichitlives

（B）thestructureofitsblossom

（C）thevarietyofproductsthatcanbemadefromit

（D）thelengthofitslife

3Theword"fused"inline2isclosestinmeaningto

（A）combined

（B）hidden

（C）fertilized

（D）produced

4Howmanyorchidseedsaretypicallypollinatedatonetime?

（A）200

（B）2,000

（C）20,000

（D）200,000

5Whichofthefollowingisakindofpetal?

（A）Thecolumn

（B）Thesepal

（C）Thestem

（D）Thelabellum

6Thelabellum（line7）ismostcomparableto

（A）amicroscope

（B）anobstaclecourse

（C）anairportrunway

（D）aracetrack

7Theword"lure"inline10isclosestinmeaningto

（A）attract

（B）recognize

（C）follow

（D）help

8WhichofthefollowingisNOTmentionedasameansbywhichanorchidattractsinsects?

（A）Size

（B）Shape

（C）Color

（D）Perfume

9Theword"their"inline13refersto

（A）orchids

（B）birds

（C）insects

（D）species

10Whichofthefollowingstatementsaboutorchidsscentsdoesthepassagesupport?

（A）Theyareeffectiveonlywhenaninsectisneartheblossom.

（B）Harmfulinsectsarerepelledbythem.

（C）Theyaredifficulttotellapart.

（D）Theymaychangeatdifferenttimes.

11Theword"placed"inline15isclosestinmeaningto

（A）estimated

（B）measured

（C）deposited

（D）identified

12Theword"discrete"inline18isclosestinmeaningto

（A）complicated

（B）separate

（C）inoffensive

（D）functional

Question13-22

Oneofthemostimportantsocialdevelopmentsthathelpedtomakepossibleashiftinthinkingabouttheroleofpubliceducationwastheeffectofthebabyboomofthe1950sand

1960sontheschools.Inthe1920s,butespeciallyintheDepressionconditionsofthe1930s,

theUnitedStatesexperiencedadecliningbirthrate-everythousandwomenagedfifteento

forty-fourgavebirthtoabout118livechildrenin1920,89.2in1930,75.8in1936,and80in

1940.WiththegrowingprosperitybroughtonbytheSecondWorldWarandtheeconomic

boomthatfollowedit,youngpeoplemarriedandestablishedhouseholdsearlierandbeganto

raiselargerfamiliesthanhadtheirpredecessorsduringtheDepression.Birthratesroseto102

perthousandin1946,106.2in1950,and118in1955.Althougheconomicswasprobablythe

mostimportantdeterminant,itisnottheonlyexplanationforthebabyboom.Theincreasedvalueplacedontheideaofthefamilyalsohelpstoexplainthisriseinbirthrates.Thebabyboomers

beganstreamingintothefirstgradebythemid-1940sandbecameafloodby1950.Thepublicschoolsystemsuddenlyfounditselfovertaxed.Whilethenumberofschoolchildrenrosebecause

ofwartimeandpostwarconditions,thesesameconditionsmadetheschoolsevenlessprepared

tocopewiththeflood.Thewartimeeconomymeantthatfewnewschoolswerebuiltbetween

1940and1945.Moreover,duringthewarandintheboomtimesthatfollowed,largenumbersofteacherslefttheirprofessionforbetter-payingjobselsewhereintheeconomy.

Therefore,inthe1950sand1960s,Thebabyboomhitananti