全新版大学英语听说教程3原文(1)(1).txt资料文档下载

全新版大学英语听说教程3原文(1)(1).txt资料文档下载

《全新版大学英语听说教程3原文(1)(1).txt资料文档下载》由会员分享，可在线阅读，更多相关《全新版大学英语听说教程3原文(1)(1).txt资料文档下载（26页珍藏版）》请在冰豆网上搜索。

llgooutwithyouagain,'

mymothersaidasIdroppedheroff,'

butonlyifyouletmebuydinnernexttime.'

Iagreed.

Howwasyourdate?

mywifeaskedwhenIgothomethatevening.

Nice...nicerthanIthoughtitwouldbe,'

Isaid.

MomandIgetoutfordinneracoupleoftimesamonth.Sometimeswetakeinamovie,butmostlywetalk.ItellheraboutmytrailsatworkandbragaboutthekidsandPeggy.Momfillsmeinonfamilygossipandtellsmeaboutherpast.NowIknowwhatitwaslikeforhertoworkinafactoryduringtheSecondWorldWar.Iknowhowshemetmyfatherthere,andknowhowtheywentthroughthedifficulttimes.Ican'

tgetenoughofthesestories.Theyareimportanttome,apartofmyhistory.Wealsotalkaboutthefuture.Becauseofhealthproblems,mymotherworriesaboutthedaysahead.

Spendingtimewithmymomhastaughtmetheimportanceofslowingdown.Peggywasright.Datinganotherwomanhashelpedmymarriage.

Questions:

1.Whatdoesthestorymainlytellus?

2.Whichofthefollowingistrue?

3.Whatcanyoulearnfromthestory?

PartC

Conversation1:

W:

Youknow,manyAmericanparentsarenowwonderingwhytheycan'

tkeeptheirteenagechildrenfromdrinking.

M:

I'

mawareofthat.Tomymind,it'

sthepermissiveattitudeoftheparentsthatistoblame.

Q:

Whatcanyoulearnfromtheman'

sresponse?

Conversation2:

m:

Don'

tyouthinkit'

sgoodtogiveourchildrenamonthlyallowance?

Ithinkso.Itcanteachthemthevalueofmoney.Withamonthlyallowancetheycanlearntobudgettheirexpenseswisely.

Whataretheytalkingabout?

Conversation3:

Mom,I'

vegotapart-timejobatasupermarket.ThreehoursadayweekdaysandalldaySaturday.

Congratulations,Tom.Butareyousureyoucanhandleit?

Whataboutyourhomeworkandyourpianolessons?

HowdoesthemotherfeelaboutTom'

spart-timejobatthesupermarket?

Conversation4:

Hey,Mary.Youlooksoupset.Whathappened?

Myfatherhadanaccidenttheotherday.Heisnowinhospitalandwillhaveanoperationtomorrow.Yousee,hisheartisratherweak.Ireallydon'

tknowwhetherhecansurviveit.

What'

sthewomanworriedabout?

Conversation5:

W:

Mother'

sDayiscomingsoon.Couldyoutellmewhatsonsanddaughtersdoinyourcountryonthatday?

Well,theysendtheirmothersflowersandcardstocelebratetheoccasion.Besides,itisacommonpracticeforthemtowearpinkcarnationsonthatday.

WhichofthefollowingistrueofthecustomsofMother'

sDayintheman'

scountry?

�ص㵥�ʼ�����

relationship��ϵencouraging������

widow�Ѹ�demandsofҪ��

curled������suspicious���ɵ�

driveway����gotaroundto���ʱ�䣨��ij�£

�

Wondering�Գ�����teenage�����

beawareof֪��attitude̬��

permissive��ɵ�toone��smind����ij�˵����

allowance����������ǮbudgetԤ��

handle���������survive�Ҵ�

occasionʱ��������carnation����ܰ

Unit3

AMarriageAgreement（PartOne）

（TomandLindahavesignedamarriageagreement.Bothagreenottobreaktherulesoutlinedintheagreement.John,areporter,istalkingtothemabouttheagreement.）

John:

Tom,Linda,firstI'

dliketoaskyouwhyyoudecidedtowritethisunusualagreement.

Tom:

Wefoundthatmanyproblemsarecausedwhenapersonhasdifferentexpectationsfromhisorherspouse.Wewantedtotalkabouteverythingopenlyandhonestlybeforewestartedlivingtogether.

Linda:

Alsowebothknowhowimportantitistorespecteachother'

spetpeeves.Like,Icangetveryannoyedifothersleavestuff--clothing,papers,everything!

--lyingaroundonthefloor.Itreallybuggedme,soweputthatintheagreement.

ThisismentionedinArticle1:

CleaningUp,isn'

tit?

Itsays,"

Nothingwillbeleftonthefloorovernight.Everythingmustbecleanedupandputawaybeforegoingtobed."

ThenI'

llknowclearlywhatLinda'

sexpectationsare.

Isee.WhataboutArticle2:

Sleeping?

Wewillgotobedat11p.m.andgetupat6:

30a.m.exceptonweekends."

msuresomepeoplehearingthiswillthinkthatthisagreementisn'

tveryromantic.

Well,wedisagree.Wethinkit'

sveryromantic.Thisagreementshowsthatwesatdownandtalked,andreallytriedtounderstandtheotherperson.Alotofproblemsoccurinamarriagewhenpeopledon'

ttalkaboutwhattheywant.

That'

sright.Whenwedisagreedaboutsomething,weworkedoutasolutionthatwasgoodforbothofus.IwouldmuchratherhaveTomreallylistentomeandunderstandmyneedsthangivemeabunchofflowersoraboxofcandy.

1.WhichstatementbestsummarizesthemarriageagreementbetweenTomandLinda?

2.AccordingtoTom,whatwillgiverisetoproblemsinamarriage?

3.WhatcanbeinferredaboutLindafromtheconversation?

AMarriageAgreement（PartTwo）

Linda,doyouspendalotoftimecheckingtoseeiftheotherpersonisfollowingtherules?

Arguing?

No,notatall.

Alotofcouplesarguebecausetheydon'

tunderstandeachother'

sexpectations.Ithinkwespendlesstimearguingthanmostcouplesbecausewebothknowwhattheotherpersonexpects.

Whathappensifoneofyoubreaksarule?

Well,that'

sinArticle13ofouragreement.

Isit?

Ohyes,Article13:

BreakingRules."

Ifyoubreakarule,youmustapologizeanddosomethingnicefortheotherpersontomakeitup."

Yeah,likelasttimeTombroketheruleofdriving.

stherule?

Theruleiswemustaskfordirectionsifwearedrivingandgetlostformorethanfiveminutes.

Whathappened?

Weweredrivingtoafriend'

swedding,andwegotlost.Lindawantedtostopatagasstationtoaskfordirections,butIthoughtIcouldfigureitout.

Thenwedrovefortymilesinthewrongdirectionandendedupbeinglateforthewedding.

SoItookherouttodinner.IknewwhatIshoulddotoapologize.

sveryimportant,Ithink,knowinghowtoapologize.Bytheway,doyouplantoupdateyouragreementatall?

Whatifthingschangeinyourlifeandaruledoesn'

tworkanymore?

We'

vethoughtaboutthattoo.Article14statesthatwemustreviewthisagreementonceayearandmakenecessarychanges.

Well,itwasreallynicetalkingtoyouboth.Thankyouverymuchforyourtime.

Tom&

Linda:

Thankyou.

Statements:

1.TomandLindaneverarguebecausetheybothknowwhattheotherpersonexpects.

2.OnceTombrokeArticle14andapologizedtoLindabytakingherouttodinner.

3.Ifsomeoftherulesinthemarriageagreementbecomeoutdated,changeswillbemadetoupdatethem.

4.ItseemsthatbothTomandLindaaresatisfiedwiththeirmarriageagreement.

APerfectMatch

Areyoulookingforagoodrelationshipwithsomeonespecial?

Whattypeofpersonisthebestpersonforyou?

IsitthepersonwiththehighestIQ?

Isitthemostbeautifulormosthandsomeperson?

Howabouttherichestpersonorthemostambitious?

Isyouridealpartnerthemosttraditionalorthemostmodernperson?

Isheorshethepersonmostlikeyou,ormostunlikeyou?

Theanswer,psychologistssay,isnoneoftheabove.Why?

Becausetheyareallextremes.Inanumberofresearchstudies,psychologistsaskedcouplesthesequestions.Theanswerswereclear.Mostpeoplearehappywithmoderation--withpartnerswhoarenotthemostorthebest（ortheleastortheworst）.Peoplearemorecomfortablewithpartnerswhoarenotsospecial.

Theresearchshowedseveralotherimportantthings.Inaloverelationship,twothingscancausetrouble.First,troublehappenswhenbothpeoplegetangryquickly.Thisisnotsurprising.Second,troublehappenswhenpeopledon'

texpecttochangethemselvesinarelationship.Doyoustaycalmwhenyoudisagreewithsomeone?

Areyoureadytochangeyourself?

Ifyoucantoleratedisagreementandarewillingtochange,maybeyouarereadyforaseriousrelationship.

1.Thepassageimpliesthattheperfectmatchforyouisapersonwhoismostunlikeyou.

2.Theauthorarguesthatthemostbeautifulormosthandsomepersonmaynotbeyourperfectpartner.

3.Moderateperson,thatis,thepartnerswhoarenotthemostorthebestcanbeyourperfectmatch.

4.Theresearchshowedthatanextremeloverelationshipbetweenthetwocancausetrouble.

5.Thepassagestatesthattheangerisoneofthecausesthatleadtothebreakupofaloverelationship.

6.Theperfectmatchliesinthepeople'

sattitudestotoleratedisagreementandbewillingtochangeinarelationship.

�ص㵥�ʼ�����

expectation�������ڴ�bug����

peeve�鷳������spouse��ż

solution����취abunchofһ��

candy�ǹ�expectation����

apologize��Ǹendup�����ԡ�Ϊ���

psychologist����ѧ��ambitious�����ĵ�moderation�ʶ�tolerate����

UNITE4

BeingaPoliceOfficerIsaStressfulJob

Interviewer:

Welcometoourprogram,Sam.

Sam:

Sam,howlonghaveyoubeenapoliceofficer?

vebeenapoliceofficerforthirtyyears.

Thirtyyears.Andyou'

vehaddifferenttypesofassignmentsonthepoliceforce,Iguess.

Yeah,I'

vedoneeverythingfrompatroltoundercoverworktodetectivework,andnowI'

msupervisinginvestigations.

Sam,Ithinkmostpeoplewouldsaythatbeingapoliceofficerisaverystressfuljob.Wouldyouagree?

Yes,it'

sdefinitelyastressfuljob.Butitdependsonyourassignment.

So,what'

sprobablythemoststressfulassignmentyoucanhave?

dsaypatrolisthemoststressfulassignment.

sinteresting!

Inwhatway?

Well,Iguessthebiggestpartofthestressisthefearfactor--thefearoftheunknown.

Whatdoyoumean,Sam?

Well,inpatrolwork,youdon'

tknowfrommomenttomomentwhoyouaretalkingtoorwhattheirreactionisgoingtobetojustifyyourpresence.Let'

ssay,forexample,apatrolofficerstopssomeoneforatrafficviolation.Itseemsasthoughthatwouldbeaverylow-stresssituation.

Yes,itisaverylow-stresssituation.

Butthetruthis,therearemorepoliceofficersinjuredduringaroutinestop.

Really?

Really!

swhyallpoliceofficersaretaughtfromtheverybeginningtobeawareoftheirsurroundings.Peoplebackoverpolicemen,peopleshootpolicemen,peoplejumpoutatpolicemen--differentkindsofthings.Sothat'

sprobablythemoststressfultime.

Isee.Let'

stakeabreakandthenwe'

llmoveontoournexttopic.

Allright.

1.What'

stherelationshipbetweenthetwospeakers?

2.WhatdoesSammainlytalkabout?

3.WhatdoyouknowaboutSam?

StressReducers

Sam,you'

vetalkedaboutthepoliceofficers'

stressfultime.Nowlet'

smoveontothenexttopic.SofarasIknow,there'

saconnectionbetweenstressandillness.Doyouthinkthatthere'

sahigherpercentageofillnessamongpoliceofficersthaninthegeneralpopulation?

Imean,dotheygetmorecoldsoranything?

Isthisreallytrue?

Yes,itis,andthestresslevelnotonlymanifestsitselfindailyhealth--whetherornotyou'

vefeelingwellonanygivenday.Italsomanifestsitselfinthingslikeulcers,heartdisease--policeofficerstendtohaveahigherrateofheartdiseaseandulcersthanpeopleinotherprofessions.

sdocumented?

Yes,it'

sdocumented.Andalsothedivorcerateamongpoliceofficersismuchhigher.

Istheresomethingthatthepolicedepartmentdoestohelpyoudealwiththisstress?

Yes,thereareseveralprogramsthatmostpolicedepartmentshaveinplace.Oneisanexerciseprogramwheresomepartofyourdayisspentonsometypeofphysicalexercise.They'

vefoundthat'

sagreatstressreducer.Besides,there'

salsoapsychologicalprogramwithcounselingforofficerstohelpthemreducetheirstress.Andthereareseveraldiscussiongroupsaswell.They'

vefoundthatsometimesjustsittingaroundandtalkingaboutthestresswithotherofficershelpstoreduceit.So,thosethingsareavailable.

Andwhatdoyoudo,personally,tohelpyoudealwiththestressofyourjob,Sam?

Well,duringthebaseballseason,I'

mthebiggestbaseballfanatic,andIwilleitherbereadingaboutbaseball,orlisteningtobaseball,orwatchingbaseball.AnotherthingItrytodoistogetsomesortofexerciseeveryday.AndthenIworkhardatkeepingupmypersonalrelationships,especiallymyrelationshipwithmywife.FortunatelyIgetalongverywellwithmywife.WhenIcomebackhome,Icantalkaboutmydaywithher,andthenjustforgetaboutit.

1.Thedialogueismainlyabouthowpoliceofficerscandealwithstress.

2.AccordingtoSam,mostpoliceofficersenjoygoodhealth.

3.AccordingtoSam,thedivorcerateamongpoliceofficersishigherthanamongpeopleinotherjobs.

4.Counselingisthemosteffectiveprogramtohelppoliceofficersrelievestress.

5.Samknowshowtoreducehisstress.

ShortConversations

1.M:

Youlooksonervous,Rose.Areyouallright?

Franklyspeaking,I'

monpinsandneedles.Ihavetogiveapresentationtoagroupofimportantvisitorsthisafternoon.

WhydoesRosefeelnervous?

2.M:

Youlooksoupset,Sue.What'

sworryingyou?

MysonJackmademeextremelyunhappy.Heseemstobeplayingvideogamesallthetime.WheneverItalktohimheturnsadeafeartome.

sthewoman'

sproblem?

3.W:

David,youdon'

tlookhappy.Anythingwrong?

Well,youknow,mymotherdiedthreeyearsago.Andsincethenmyfatherhaslivedinanapartmentonhisownandhasveryfewfriends.

WhatisDavidworryingabout?

4.W:

Michael,Idon'

tknowwhathashappenedtoMother.Hermemoryseemstobegoing.Ihavetoremindherofalmosteverything.

tworry,Mary.She'

sjustgettingold.

WhatdoyouknowaboutMary?

5.W:

mworriedaboutsendingmysonPetertocollege.Yousee,nowadaysmanycollegestudentsbehaveratherstrangely.Theydon'

tseemtobeinterestedintheirstudies.

Justafew.Moststudentsstillconcentrateontheirstudies.

Whatcanyouinferfromtheman'

�ص㵥�ʼ���

assignment���䣬����patrolѲ��

undercover���ܴ��µ

�detective��̽

supervise�ල������investigation���飬�о�

definitely��ȷ�أ��ɴ��reaction��Ӧ������

violation������manifest����

ulcer����,������counseling��ѯ����

fanatic���ȵ�

franklyspeaking̹�ʵ�˵onpinsandneedles������ձ

turnsadeafearto��������remindof���ѣ�ʹ�ǵ�

concentrateon���У�ȫ���ע��

Unit5

Ashley

AshleywasreadingamagazinewhenshecameacrossanarticleaboutantibioticsandotherdrugsdiscoveredinEuropeanriversandtapwater.Ifsuchdrugswerepresentthere,shereasoned,theymightalsobefoundnearherhomeinWestVirginia.

Ashleyfearedthatantibioticsinthewaterscouldleadtoresistantbacteria,orsupergerms,whichcankilluntoldnumbersofpeople.

Thegirl,then16,begantestingherarea'

sriver--theOhio.Withasimpledevicesheherselfhaddesigned,shecollected350watersamplesfromtheOhioanditstributariesovertenweeks.Readingscientificjournals,shetaughtherselftoanalyzethesamples.Itwasthemostscientificallysoundprojectforsomeoneherage.

Herexperiment,oneofthefirstofitskindintheUnitedStates,showedthatlowlevelsofthreeantibioticsareindeedpresentinlocalwaters.Ashley'

sstudywontheInternationalStockholmJuniorWaterPrize,avirtualNobelPrizeforteenagers.Shereceiveda$5,000scholarshipandanaudiencewithSweden'

sCrownPrincessVictoria.

Herinterestinsciencewassparkedbywalksinthewoodswithhermother.Butitwastheday-to-daystuff--howwatercomestothetap,howrainstickstoglass,thatmostfascinatedher."

Scienceisnotadeadthing,"

shesays."

It'

shappeningallaroundus."

Bythesixthgrade,shewaswinningatsciencefairs.Shehaswon$70,000inprizemoney,whichshehasputasideforcollege.SheplanstoattendHarvardUniversity."

Iwanttomakemyowndiscoveries,andnotjustreadaboutwhatothershavedone,"

shesaid.HerteacherspredictthatshewillonedaywinaNobelPrize.

1.AshleylivesinthestateofVirginia.

2.Antibioticsinstreamsandriverscanleadtotheemergenceofsupergerms.

3.BacteriafoundinEuropeanlocalwatersandtapwaterhavekilledcountlesspeople.

4.Usingsimpleequipmentdesignedbyherself,Ashleycollected350watersamplesintenweeks.

5.Ashley'

sexperimentprovedthatantibioticsdidexistintheOhioRiver.

6.Ashleydevelopedastronginterestinsciencewhenshewasinhersixthgrade.

7.Ashleywantstomakediscoveriesbyherselfandknowshowtomakeuseofwhatshehasread.

8.TheInternationalStockholmJuniorWaterPrizeisaNobelPrizeforteenagers.

9.Ashleygota$5,000scholarshipfromHarvardUniversity.

10.Ashleycanberegardedasarolemodelforyoungpeople.

YoungPeopleSayNotoSmoking

OnFebruary16,2001,theteensfromayouthgroupcalledREBELlaunchedtheiradvertisingcampaignattheLibertyScienceCenterinNewJersey.Bynowjustabouteverybodyhasheardthe"

NotforSale"

commercialontelevisionandtheradioagainsttobaccocompanies.Whatmanypeopledon'

tknowisthatteenagersfromWestNewYorkandacrossNewJerseyworkedonvariousaspectsofthecampaign,andevenappearedinsomeoftheadvertisements.ThecampaignorganizerthoughtitwouldbebetterthanusingactorsifactualREBELmemberswereinthecommercials.

REBEL,whichstandsforReachingEverybodybyExposingLies,isastatewideyouthinitiativeagainsttobaccocompanies.Themovement,whichbeganinNovemberlastyear,carriesthemessagethatteensnolongerwanttobetargetedbytobaccocompaniesintheiradvertisements.Knowingthatpeerpressureonteenstosmokeordodrugsisoneofthebiggestproblemsthatteensface,thegroupisworkinghardtoensurethattheirmessagereachesallteenagersatNewJerseyschools.

Whenthegroupwasfirstformed,therewereonlyfivemembers,alleighthgradestudents.Butbythissummerthegrouphadgrowntocloseto90members.Atarecentrecruitingparty,apizzaandpoolparty,attheWestNewYorkswimmingpool,morethan50newmemberswereattractedtothegroup.

"

Wedon'

tthinkthattoomanypeoplewouldbeinterested,"

saidJackie,oneofitsfoundingmembers."

Buteveryoneknowsourmessage.Theyknowwhowearenow."

1.WhendidREBELlaunchtheiradvertisingcampaign?

2.HowmanymembersdidREBELhavebythesummerof2001?

3.WhoarethemembersofREBEL?

4.WhatdidREBELdofortheircampaignagainsttobaccocompanies?

5.WhatdidREBELdorecently?

Skatescooters

InHongKongthesedays,youwilloftenseepeopleridingskatescootersinthestreets.Dependingonwhichwayyoulookatthem,theycanbegreatforperformingtricksorarejustthelatestfashionablecommodity.Fungisoneofthemoreexperiencedskatescooterriders,ashehasbeenpractisinghistechniqueforaboutayear.Hiscurlyhairandbaggyjeansshowhisdevotiontostreetfashionandbeingcomfortable.Hehasadeeppassionforandunderstandingofthissport.

Istartedridingskatescooterayearago,butatthattimetherewasnoonetosharetheexperiencewithorlearnnewtricksfrom,"

heexplained."

Nowthatithascaughtonandmorepeopletakepartinit,itismoreenjoyable."

MostofthebestbrandsofskatescootersaremadeinSwitzerlandandbegantobeimportedtoHongKongin1999.Noonetookmuchnoticeofthem,however,untiltheybecamepopularinJapan.WhenpeoplesawskatescootersinJapanesemagazinestheyweresoontryingtobuytheminHongKong.VeryquicklyHongKonghaditsowngroupofskatescooterridersandthenumberisstillgrowing.

However,notallwhoenjoyskatescootersregardridingthemasasport.Forsomepeopletheyaresimplyaquickwaytogetfromhometotheundergroundorfromabusstoptotheoffice.Astheycanbefoldedupwithoutdifficultyandareeasytocarryabout,theyhavebecomepopularwithavarietyofpeoplefromschoolstudentstobusinessexecutives.

1.SkatescootersareverypopularinHongKong.You'

llfindridersperformingtricksonskatescootersinthestreets.

2.FungisthepersonwhointroducedskatescooterstoHongKong.

3.FungisadevotedperformerandthemostskillfulriderofskatescootersinHongKong.

4.IttookFungaboutayeartopractiseandbecameoneofthemoreexperiencedskatescooterridersinHongKong.

5.MagazinesplayanimportantroleinpopularizingskatescootersinJapan.

6.Nowskatescootershasbeenlistedasoneofthecompetitivesportsaroundtheworld.

7.Peopleliketorideskatescootersasasportaswellasaconvenientmeansoftransportation.

cameacrossż��antibiotic������

resistant�ֿ��ģ��еֿ���bacteriaϸ��

fascinateʹ����putasideƲ��

commercial��ҵ��statewide�鼰ȫ�ݵ�

recruiting��ļ�ױ�,��ԭinitiative����

trick��ƣ���ƭ

commodity����Ʒ

regardas�ѡ�����

executiveִ����

Unit6

WhyDoLeavesChangeColor?

Insomeplaces,asdaysshortenandtemperaturesbecomecrisp,thequietgreenofsummerfoliageistransformedintothevividautumnofreds,oranges,yellowsandbrownsbeforetheleavesfalloffthetrees.Inspecialyears,thecolorsaretrulybreathtaking.

Buthaveyoueverwonderedhowandwhythishappens?

Toanswerthatquestion,wefirsthavetounderstandwhatleavesareandwhattheydo.

LeavesareNature'

sfoodfactories.Plantstakewaterfromthegroundthroughtheirroots,andcarbondioxidefromtheair.Thentheyturnwaterandcarbondioxideintoakindofsugar,usingsunlightandsomethingcalledchlorophyll.Thisprocessiscalledphotosynthesis.Aschlorophyllisgreen,leavesarethereforealsogreenincolor.

Duringwinter,thereisnotenoughlightorwatertohelpplantsproducesugarastheirfoodforenergyandasabuildingblockforgrowing.Thetreeswillrest,andliveoffthefoodtheystoredduringthesummer.Thegreenchlorophylldisappearsfromtheleaves.Asthebrightgreenfadesaway,webegintoseeyellowandorangecolors.Smallamountsofthesecolorshavebeenintheleavesallalong.Wejustcan'

tseetheminsummer,becausetheyarecoveredupbythegreenchlorophyll.

Thebrightredsandpurplesweseeinleavesaremademostlyinfall.Insometrees,likemaples,sugar,whichisproducedintheleavesduringwarm,sunnydays,iskeptfrommovingoutoftheleavesafterphotosynthesisstops.Sunlightandthecoolnightsoffallturnthesugarintoaredcolor.Thebrowncoloroftreeslikeoaksismadefromwastesleftintheleaves.

Itisthecombinationofallthesethingsthatmakesthebeautifulcolorsweenjoyinfall.

1.Whatisthepassagemainlyabout?

2.Whichofthefollowingplaysamajorroleinmakingleaveschangecolor?

3.Whycan'

tweseeyellowandorangecoloursinleavesduringsummer?

4.Whichofthefollowingbestdescribesthespeaker'

sattitudetowardhissubject?

TimingofColorChangeinTrees

Manytreesandshrubschangecolorinfall.Foryears,scientistshaveworkedtounderstandthechangesthathappentothem.Theyfindthatthreefactorsinfluencefall'

scolorfulfarewell--leafpigments,lengthofnight,andweather.Thetimingofthecolorchangeismainlyregulatedbytheincreasinglengthofnight.Noneoftheotherenvironmentalinfluences,suchastemperature,rainfall,foodsupply,areasunchangingasthesteadilyincreasinglengthofnightduringfall.Asdaysgrowshorter,andnightsgrowlongerandcooler,biochemicalprocessesinleavesbegintopaintthelandscapewithanexplosionofcolors.AndNatureputsononeofitsmostspectaculardisplaysofbeauty.

Thetimingofthecolorchangevariesbyspecies.Somespeciesinsouthernforestscanbecomevividlycolorfulinlatesummerwhileallotherspeciesarestillvigorouslygreen.Oaksputontheircolorslongafterotherspecieshavealreadyshedtheirleaves.Thesedifferencesintimingamongspeciesseemtobegeneticallyinherited,foraparticularspecies,whetheronahighmountainorinwarmerlowlands,willchangecoloratthesametime.

However,somespeciesareevergreens.Pines,forexample,aregreenalltheyearroundbecausetheyhavetoughenedup.Theyhavedevelopedovertheyearsaneedle-likeorscale-likefoliage,whichiscoveredwithaheavywaxcoating.Andtheliquidinsidetheircellscontainscold-resistantelements.Sotheleavesofevergreenscansafelywithstandallbutthemostseverewinterconditions,suchasthoseintheArctic.

1.Whatdoesthespeakermainlytellus?

2.Whatarethetwomajorkindsoftreesthatthespeakerdifferentiates?

3.Bywhatisthetimingofthecolorchangemainlyregulated?

4.Whydosomespeciesoftreesremainevergreen?

PartC

TheMissingMonarchs（PartOne）

Themonarchbutterflyhasrichorange-goldwingsoutlinedinblackanddecoratedwithsmalldotsofwhite.Itlookslikeastained-glasswindowthathascomealiveasitfluttersthroughthesummersunshine.

AcrossmostoftheUnitedStatesandCanadamonarchstakealongjourneysouthwardwhenthecoldseasonsetsin.

MonarchsfromthewesternUnitedStatestraveltoawinterhomeontheCaliforniacoast.Butuntilrecently,noonehadeverseenthewinterhomeoftheeasternmonarchs.Formorethanfortyyears,aToronto-basedCanadianzoologist,FredUrquhart,triedtosolvethepuzzlingmysteryofthemissingmonarchbutterflies.Hisfirststepwastomarkthebutterflies.Ittookalongtimetofindawaytoattachtagssothetagwouldstayinplaceandthebutterflycouldstillfly.Manypeoplevolunteeredtohelp.Theycaught,tagged,andsetfreeagainthousandsofbutterflies.Eachtagboreacodetoindicatetheexactplacewherethebutterflyhadbeentagged.AmessagealsoaskedanyonewhofoundthetaggedbutterflytosendtheinformationtoanaddressinToronto,whereitwouldreachthezoologist.Thus,thetagsweretoserveasthescientist'

sclues.

Theirdetectiveworkpaidoff.Overtheyearstheylearnedagreatdealaboutthemigrationoftheeasternmonarchbutterflies.Theseseeminglyfragilecreatureshavebeenknowntocovereightymilesinasingleday!

Theycanflytenmilesanhour,andsomehavebeenclockedatthirtymilesanhour!

Thebutterfliestravelandeatduringtheday.Whenitcoolsoffatnight,theyrestintrees.Themorningsunwarmsthem,andtheycontinuetheirmigration.

SomeofthebutterfliesweretracedsouthacrossFlorida.ManyweretracedthroughTexasintoMexico.Buttherethetrailwaslost.

1.Themonarchbutterflieshaveorange-gold,blackandwhitecolorsontheirwings.

2.Accordingtothepassage,scientistsfailedtofindthewinterhomeofmonarchsfromwesternUnitedStates.

3.TheCanadianzoologist,FredUrquhart,spentseveraldecadestryingtosolvethemysteryofthemissingmonarchbutterflies.

4.Urquhartandmanyvolunteersmarkedthousandsofbutterfliesbyattachingtagstothem.

5.EachtagboreacodenameandtheaddressofUrquhart'

sTorontohome.

6.Thebutterfliescanflytenmilesanhourandsomecanevengoateightymilesanhour.

7.Thebutterfliesareactuallytougherthanweexpected.

8.Thescientistlostthetrailofthebutterflies,thoughsomeweretracedsouthacrossFloridaandmany,throughTexasintoMexico.

crisp����ģ�foliage��Ҷ��ֲ��

carbondioxide������̼photosynthesisҶ����

chlorophyll�������combination������

shrub��ľpigmentɫ��,����

timing��ʱbiochemical���ﻯѧ��

landscape�羰spectacular������ʤ��

vigorously������ʢ��

stained-glass��ɫ�IJ���volunteer־Ը��

fragile�����detective��̽

migration������ֲzoologist����ѧ��

hectic�˷ܵ�essential���ʵ�

terminal�ն�counselor����