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Unit1Happiness

Part1

TEACHER:Hi,goodmorning.Didyouhearaboutthe

lotterywinnerlastnight?Themanwon...what?...

Tvomilliondollars...?

STUDENT:No,three.

TEACHER:Threemilliondollars?Threemillion.That'salotofmoneyisntit?Doyouthinkthatthreemilliondol-larswouldmakeyouhappy?...I'maskingyouthisbecausewhenyouaskpeoplewhattheyneedtobehappy,manypeoplewillanswer"moremoney!"Weassumethatmoneywillmakeushappier.Butisthistrue?Willwin-ningthelorteryhelpyouachicvehappiness?

Todaywe'regoingtolookattheideaofhappiness,atthe

psychologyofhappiness—whatmakessomepeoplehap-

pierthanothers.Welllookatthreepersonalityfactors

thatwefindinhappypeople.Tofindouraboutthesepersonaliyfactors,psychologiststalkedtohundredsofpeople.Now,first,theyaskedthepeoplehowhappytheyfelt—youknow,from"veryhappy"to"nothappyarall."Thentheyaskedsomemorequestions.Theywantedtofindoutaboutpcople'spersonalities,suchastheirattitudesaboutlife,andsoon.Theylookedatthediffer-encesbetweenhappypeopleandunhappypeople.Theyfoundthreefactorsthatareveryimporrantforachicvinghappiness.So...let'slookatthosefactorsnow.

Buttheproblemis—theyneverfindit!Nomattcrwhattheyget,they'resilldissatisficdandunhappy.

Thesecondpersonaliyfactoristhathappypeopleare

optimistic—theylookatthepositivesideoflife,notthe

negative.Now,weallhaveproblems,whetherwe're

happyornor.Butwhenhappypcoplehaveproblems,

theyassumethatthingswillimprove.Theydon'tworry

alorandthinkaboutallthebadthingsthatcanhappen.Instead,theyhaveapositiveattitude.However,unhappypeoplearetheopposite.Theyarenotoptimisticanddon'thaveapositiveattitude.Whentheyhaveaproblem,theythinkabouthowbadevery-thingisandassumethatit'llgetworse.Sotheymakethemselvesevenmoretnhappywhentheythinkaboutallthebadthingsthatmighrhappen.

Finally,thethirdpersonaliryfactoristhathappypeoplehavegoodrelationshipswithotherpeople.Theytrytohavecdose,lovingrelationshipswithfriendsandfamily.Studiesshowthatclose,lovingrelationshipsareoneofthemostimporrantfactorsinachicvinghappiness.Sohappypeopledon'tspendalltheirtimebuildingtheircareersortryingtomakemoney.Theyalsospendtimebuildingrelarionshipswithfriendsandfamily.Now,ontheotherhand,unhappypeopledon'thaveasmanydoserelationships.Theymayhavetroublemakingfriends.Ortheymayspendalltheirtimeworkingandthenfindthatthey'reverylonelyandunhappy.Butforwhateverreason,theydonthavecloserelationsbipsandthismakesthemunhappy

Thefirstpersonaliryfactoristhathappypeopleare..

satisfiedwiththemselves.Thismeansthattheylikethemselvesastheyare,andthey'rehappywithwhattheyhave.Happypeoplemaynotlikeeverythingabouttheirlives—theymaybealitdlebitoverweight,ormaynothavethebestjob,ormaynotliveinabig,fancyhouse,buttheydontnedtochangethosethingstobehappy.Theythinkmoreaboutthethingstheyaresatisfiedwith,notthechangestheywanttomake.Thisfeelingofhappinesscomesfromtheinside,notfromsomethingoutside.

So...whatdoesthistellus?Well,ifyouwanttobehappier,don'tasumethatwinningthelotterywillhelp.Thereareother,moreimportantfactorsforachievinghappiness.Now,let'stakeabreak,andwhenwecomebackwe'lltalkmoreaboutthefactorsthatmakeapersonhappy.··

Unit2NewKindsofFood

Part1

Part2

TEACHER:So...happypeoplefeelsatisfiedwiththemselves.Ontheotherhand,unhappypeopleareoftendissatisfiedwiththemsclves.They.uhfeelthatsomethingmustchangesotheycanbehappy.Theythinkiftheylosesomeweightorgetabetterjoboranicerhousetheywillbehappy.Theyarealwayslookingforsomethingoursidethemselvestomakethemhappy.

TEACHER:Hi,everybody...howsitgoing?....Good....Haseveryoneturnedintheirhomework?Allrighty,thenlet'sgetstarted.Ifyouremember,lastweekwewerediscussingsomeresearchintheareaofgenetics.Today,IdliketotalkaboutsomethingI'msureyouveallheardabout—geneticallymodifiedor“GM”food.Geneticallymodifiedfoodisfood-eitheraplantorani-mal-thathasbeenalteredinthelaboratorybyscien-tists.Thescientiststakesomethingfromoneplantor

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animal,andaddittoadifferentplantoranimaltomaketgrowinadifferentway.Today,we'lllookatsomeofthebengfis,andtheposiblerisks,ofgeneticallymodifiedfood.

LetsstartwithadiscussionofsomeofthebenefitsofGMfood.Geneticscientistsarereallytryingtomakefoodplantsthatarebetterthannormalplants,tomakeplantsthatarealteredinwaysthatmaketheplantgrowberterortastebetterorbehealthiertoeatthannormalplants.

Onebenetitisthargeneticallymodifiedplantsmayneed

fewerpesticidesthannormalplants.Forexample,there

isatypeofcornthatisbadforinsects—whentheinsectseatthecornplant,theydie.However,thecorndoesnthurtpeople.Thisrypeofcornisbeneficialbecausefarm-

ersusefewerpesticidestogrowthecorn,andsothereis

lesspollurionintheenvironment.Alsothecornisless

expensivebecausethefarmersdon'thavetospendalotof

moneyonpestirides.So,byusingfewerpesticides,the

cornischeaperandtheenvironmentiscleaner.

Anotherbenefitofgeneticallymodifiedplantsisthattheymaygrowbetterthannormalplants.Oneexampleisaypeofgeneticallymodifiedstrawberrythatcangrowincoldweather.Thesearebetterthannormalstrawberriesbecausefarmerscanplantsthestrawberriesearlierinthespringandlaterinthefll,whennormalstrawberriesusu-allydie.So,asaresult,farmerscangrowmanymorestraw-berriesthantheyusedto.Sothatsanotherbenefit—plantsthargrowbetter.

Finally,athirdbenefitisthatmanygeneticallymodifiedplantsstayfreshlongerafertheyareharvested.So,forexample,thereisakindoftomatothatstaysfreshinthestoreforabouttwomonths,insteadofoneortwoweeks.Thismeansthatthereismoretimetogetthefoodtothe

storesandthatstoreshavemoretimetosellthefood.

Lessfoodisthrownawayandwasted.Soit'sagreat

benefittohavefoodthatstaysfreshlonger-andwecanconsumemoreofthefoodwegrow.

Part2

TEACHER:Nowthatwe'velookedatsomeofthebenefitsofgeneticallymodifiedplants,let'stalkabouttherisksofgrowingthisypeoffood.Wedon'treallyknowwhattheharmfuleffectsare,butthereareseveralthingsthatpeo-pleareworriedabout.

Oneriskisthatthegeneticallymodifiedplantsmaystarttodominatetheotherwildplantsintheenvironment.Thisisaproblemwithsometypesoftomatoes,forexam-ple.Thenewtomatoplantsarestrongerthannormalplants,andbecausetheyarestrongerandgrowfasterthanthewildplants,thegeneticallymodifiedtomaroes

maystarttodominatetheenvironment,causingthewildplantstodic.Sohavingoneplantdominatealltheotherplantsisnitgoodfortheenviromment.

Anotherriskisthatgeneticallymodifiedplantswillhurtwildanimalsandinsectsintheenvironment.Forexam-ple,thegeneticallymodifiedcornImentionedearlierhasalreadycausedthisproblem.Nowsomebutterfliesthatlivenearthecornaredying—butterfliesthataregoodinsects,anddon'teatthecorn.It'spossiblethatcorniskillingthebutterfliessomehow,butwe'renotsure.Wejustknowthatmorebutterfliesaredyingthannormal.Butdearlythere'sariskthatgeneticallymodifiedfoodscanhurtanimalsandinsectsintheenvironment.

Butprobablythemostimporrantriskisthatgeneticallymodifiedfoodmaybeharmfulrothepeoplewhoconsumethefood.Thealterationsintheplantsmaycauseseriousproblemsforpeople—wejustdontknow.Scientistsaretryingallkindsofnewthings,suchasput-tingthegenesfromanimalsintoaplant.Forexample,tomakeafruitlikestrawberriesstayfreshlonger,scientiststookagenefromafish—agenethathelpsthefishliveincoldwarer—andpurthatintoastrawberry.Willthatstrawberrybeharmfultopeople?Wedon'tknow.Butitmaybe

Soit'sclearthattherearesomeimportantbenefitstogeneticallymodifiedfoodbutalsosomerisks—risksthatalotofpeoplearen'twillingtotake.Soletsstophereanddiscussanyquestionsyouhaveatthispoint..

Unit3PublicArt

Part1

TEACHER:Goodmorningeverybody.Ihopeyouallenjoyedourtriptotheartmuseumlastweek.Todaywe'regoingtotalk...uh...moreaboutmodernart.Well...uh...takealookatsomeexamplesofpub-licart—artyoucanonlyfindoutdoors...uh...inpublicplaces.I'llexplainthepurposeofpublicart,and...uh...thenIlldescribesomeexamplesofpublicartthatillustratethreecommontypesofmodernart:popart,realim,andsurrealism.

Burfirst,publicart....Thesedayspublicartisbecom-ingmoreandmorepopular.Manybusinessandcityleadersareputtingupartinpublicplaces-inparksandgardens,nearofficebuildings,andsoon.Citiesliketoputartinpublicplacesforacoupleofreasons.Um...firstofall,arthelpstomakeourcitieslookmorebeauti-fulandinteresting.Also,whenartisourdoors,manypeoplecanlookatitandenjoyiteveryday;theydon'thavetogotoamuseum.Sohavingartinpublicplacesletsmorepeopleenjoyarteveryday.

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Now,I'mgoingtomoveontosomeexamplesofpublicart.Here'sourfirstexample—asilverspoonandaredcherry.Thispieceishuge:It'srwenry-ninefeetwideandoverfifryfeetlong!It'smadeofmetal—steelandalu-minum.Itspaintedsilverandbrightredtolqoklikeaspoonwitharedcherryonit.Thesculptureisagoodexampleofpopart.Popartistsliketomakearttharshowspopularthings—thingspeopleseeintheirevery-daylives.Thisartistlikestotakecommonobjects,likefood.andmakethemintohugesculptures.Sowhardoyouthinkaboutit?Anyone?

STUDENrI:Ithinkitsgreat!Itsreallyunusual.Ilikeitbecauseitssimpleandeasytounderstand.

TEACHER:Yes,that'swhymanypeoplelikepopart.Anyotheropinions?Yes...Mark?

STUDENT2:Well,IthinkitsOK,butI...Ithinkartthatisoutinpublicshouldbesomethingimportant,somethingthat'sverybeautifulorthatmeanssomething.

Itshouldn'tjustbejustsomeeverydaything,like...aspoon.

TEACHER:Interestingpoint.Soyoucanseethatoneproblemwithpublicartistharpeopleinterpretthepur-posedifferently-theydisagreeaboutwhatitshouldlooklikeormean.Andsomepeoplemaylikeorunder-standapieceofart,whileotherpeoplemaynotlikeitatall.

Part2

TEACHER:AsIalreadymentioned,onepurposeofpublicartistoaddbeautytopublicplaceswhereeveryonecanenjoyit.Butanotherpurposeofartistoillustrateideasorconcepts—toshowsomekindofmeaningInsteadofusingwords,artistscansendmessagesthroughtheirarttopeoplewhoseeit.Sometimes,artistsevenusetheirarttopromotetheirownbeliefs.Togiveyousomeexam-

ples,hereareacoupleofsculpturesthatweremadeto

promotetheconceptofpeac.Thefirstoneisalarge—

aboutsixteen-foottall—metalsculpturethatshowsayoungwomanonahorse.Noticehowrealandlifelikethefeaturesofthewomanandthehorselook.Becausetheyaresorealistic,wecallthisstyleofartralism.Butthewomaninthissculptureisactuallyasymbolfor

peace.Sointhisexample,theartisrealisticand

symbolizesaconcept-theconceptofpeace.

Anyquestionssofar?...OKthen.Letstakealookatanothersculpturethatwasmadetopromotetheideaofpeace.It'salsomadeofmetalandlookslikeagun.Itsalittlesmallerthanthefirstexample.It'saboutsixfeetwideandthirteenfeetlong—bugeforagun.Itlooksjustlikeagun,untilyounoticethatitistiedintoaknotattheend.Weallknowthatitisimpossibletotieagun

intoaknot,right?Andso,becauseit'simpossible,thissculpureisagreatexampleofsurrealism.Also,asyouknow,agunitselfdoesn'tsymbolizepeace.However,becausethegunistiedintoaknorandcantbefired,it

illustratestheconceptofpeace

Andso,inthesethreeexamples,wecanscehowpublicartcanbeusedtomakeourcitiesmorebeautifulandinteresting,andwecanseehowpublicartcancommuni-careideasorcomceptstopeople.Let'stakeabreaknow.andwhenwecomebackwe'lllookatsomemoreexam-plesofmodernsculpture...

Unit4JourneytoAntarctica

Part1

TEACHER:Goodafternoon.Pleasetakeyourseats.Ihavealottodiscusstoday.TodayI'mgoingtotalkaboutoneofthegreatestadventuresofthetwentiethentury—ErnestShackleton'striptoAntarctica.Now,thereareotherexplorerswhohavebeentoAntarctica,butShack-eton'stripisespeciallyinterestingbecausehisgoalwastobethefirstpersontowalkacrossthecontinentofAntarc-tica.Also,asyou'llfindout,thistripwasalsospecialbecauseoftheproblemsanddifficultiesthatShackletonandhiscrewenduredalongtheway.Infact-andthisisinteresting—ShackletonmadehistriptoAntarcticaonashipcalledtheEndurance.It'salmostasifhesomehowknewaboutthedifficulteventstocome.

Letsbeginin.England.TheEnduraneeleftLondonin1914withacrewoftwenty-ninemen,sixty-ninesleddogs,andacat.AfterstoppinginArgentina,theshipproceededtoSouthGeorgia,anislandabout800milesfromAntarctica.Then,onDecember5,1914,theEndurancelcftSouthGeorgia.Andrightaway,theshipenteredwaterthatwasflledwithice.However,despitethedanger,Shackletonandhiscrewproceededontheirjourney.ShackletonbelievedthattheycouldreachtheAntarcticcontinentdespitetheice.Hewaswrongabout

this,however,andonJanuary18,1915,astheEndunance

approachedAntarctica,itbecamestuckintheice;it

couldn'tgoanywhere.Thecrewstayedontheship,whichfoatedalongwiththeiceformorethantenmonths.Duringthattime,thecrewlivedontheship,althoughtheycouldgodownontheiceandwalkaroundifitwasnottoocold.

OnOctober27,1915,Shackletonorderedthecrewto

leavetheEndurance.Theytookfoodandothersapplies

(includingthreesmallerboats)offtheshipandsetupcamponalargepicceoffoatingice.Thisturnedouttobeagooddecision,becausejustamonthlater,theywatchedastheirshipwascrushedbytheiceandsankunderthewater.

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Part2

TEACHER:So...iseveryonewithmesofar?Anyques-tions?...OK,thenlet'scontinye.Forthenextsixmonths,thecrewoftheEnduranclivedontheicefoat-ingaroundtheedgeofAntarctica.Theyatethefoodfromtheship.butwhenthatwasgone,theyhuntedani-malsintheareaandfinallykilledandatetheirdogs.Finally,inAprilof1916,thecrewsawland.ItwasEle-phantIsland,whichwasabout100milesaway.Theyknewthattheicebelowthemwasgettingthinnerandmightbreakatanytime,sotheydecidedtoproceedtotheisland.

So,onApril9,1916,ShackleronandhiscrewgotintothethreesmallboatstheyrescuedfromtheEndurancebeforeitsank.TheyputalltheirsuppliesintheboatsandbeganthejourneytoElephantIsland.Ittookthemsevendaystogetthere.Thejourneywasterribleandthey

violenceinthemediabyfocusingontelevision—onTVviolenceanditsimpactonchildren.FirstI'lldiscusshowmuchviolenceisonTV.andthenwe'lltalkabouttheimpactofTVviolenceonchildren.There'salorofdebateaboutthisissuetodaybecausechildrenwarchalotofTV,right?

TVhasahugeimpactonchildren;kidstodaywatchulotofTV.IntheU.S..almostallfamilieshaveaTV—ninty-cightpercent.ManyfamilieshavemorethanoneTV.Fifty-rwopercentofchildrenhaverelevisionsintheirbedrooms,sotheycanwarchTVwhenevertheywant.AndhowmuchTVdocstheaveragechildwatchcachday?Cananyoneguess?

STUDENT1:Twohours?

TEACHER:OK,thatsoneguess.Anyoneelse?

STUDENT2:Four?

allalmostdied.

Sonowthecrewwasonland,buttherewasnohopethartheywouldberescuedfromElephantIsland.Itwastoofarawayfromanything.ThenearestpeoplewereonSouthGeorgiaIsland,over800milesaway.Despitethedanger,ShackletondecidedtogotoSouthGeorgia.Heknewitwastheironlyhopeforrescue.SoonApril24,1916,ShackletonandfivemenleftinoneofthesmallboatstotrytogettoSouthGeorgia.TwenrymenstayedonElephantIsland.

Afterseventeendaysinstormyseas,ShackletonandhismenreachedSouthGeorgia.Buttheyweren'tfinishedyet-theyhadtowalkforthirry-sixhourstoreachthewhalingstation.Finally,onMay20,theyreachedthewhalers.Butremember—ShacklctonstillhadtorescuehismenonElephantIsland.Thistookmorethanthreemonths.ThreeshipstriedtogettoElephantIsland,buttheycouldn'tgertherebecauseofalltheice.

Finally,onAugust30,1916—twenty-twomonthsaftertheyleftontheirjourney—Shackletonrescuedhismen.Amazingly,everyoneontheislandwasaliveandtheywereallrescued.It'shardtobelieve,isn'tit?So,asyousee,thisisanimportantandinterestingexampleofexplorationfromthelastcentury.

Nowletstakealookatsomeotherfamousexplorersofthewentiethcentury..

Unit5ViolenceonTelevision

Part1

TEACHER:Hello,everyone.Areyoureadytogetstarted?...OK.TodayIdliketocontinueourdiscussionof

TEACHER:Yes.Itsabout...aboutthreetofourhoursofTVeveryday,oralmost1.500hoursayear.Now.comparethattotheamountoftimethatkidsspendinschooleachyear,about900hours,andyoucanseetharTVmusthaveabigimpact

Now,manypeoplefeelthatchildren'sshows,suchascar-toons,aremuchtooviolent.Somepeopleevenfeelthattheviolenceontelevisionisteachingkidstobemorevio-lent.Buristhistrue?IstherealinkberweentheviolencechildrenseeonTVandrealviolence?Toanswerthisquestion,Iwanttofocusonsomeoftheresearch—researchthathasbeendonetoassesstheviolenceontel-evisionandhowitaffectschildren.

ToassesshowmuchviolenceisonTV,researchhas

focusedoncountingthenumberofactsofviolenceon

TVinanaverageday.Now,thisindludesanyactthatcouldhurrorkillpeopleinreallife.Surprisingly,car-toonsforchildrenhavethemostviolence—morethanmanyshowsforadults.Cartoonshaveanaverageof

thirty-twoviolentactsperhour.So,thirty-twotimes

everyhour,onecartooncharacterhurtsanother

chanacterinsomeway.Well,you'veseenthisincartoons,I'msure.Thecharactershitcachotheronthehead,orshooreachother...manydifferentviolentacts.

Otherkids'showshavealotofviolenceaswell.Forexample,manykids'showshavecharactersthatfightcachother—hitandkickandpuncheachother—sothoseareveryviolentaswell.

Part2

TEACHER:So,bycountingalltheseactsofviolence,wecanestimatethatbythetimeachildisrwelve,heorshewillhaveseenanaverageofabout100,000actsofvio-lenceontelevision.Thatsaboutthirtyviolentactsper

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day!Butdoestheviolencereallycausechildrentoactmoreviolently?Well,thatleadsustooursecondques-tion:HowdoweassesstheimpactofTVviolenceonchildren?

First,we'llfocusonsomeimmediateeffectsofwatchingTVviolence—wharhappensimmediatelyafterachildwatchessomethingviolentonTV.Inthefirstsrudywe'llookartoday.agroupofchildrensawaTVshowofachildhittingandkickingadoll.Then,aftertheywatchedthevideo,eachchildwasleftaloneinaroomwiththesametypeofdoll.Andguesswhat?Allthechildreninthissrudy—100percent—hitandkickedthedoll,justliketheysawonTV.Sothelinkhereberweenwhatkidsseeandwhattheydoseemsquitestrong.

AnotherwaytoassesstheeffectsofTVviolenceonchil-drenistofocusonthelong-termeffects—whathappensmanyyearsafterachildwatchesviolentTV.Nowler'stalkaboutthesecondstudy.In1960,researchersstudiedeight-year-oldchildreninatypicalAmericancity.TheystudiedhowmuchviolentTVthechildrenwatchedandwhetherthechildrenactedviolentlyathomeoratschool.Then,tenyearslarer,theystudiedthesamechil-drenatagecighteen.TheresearchersfoundthatchildrenwhowatchedalotofviolentTVatageeightweremoreviolentatageeighteen.Childrenwhowatchedlessvio-lentTVwerelessviolentatageeighteen.SothisstudysuggeststharthereisalinkbetweenTVviolenceandreal

violence—thatwarchingviolentTVhaslong-term

impactonthesekids.

SodothesestudiesprovethatTVviolencecauseschil-drentobeviolent?Evenwiththeresearch,manypeoplestilldisagreeaboutthat.So,whenwecomeback,welltalkmoreabouttheimpactofTVviolence...

Unit6TooOldtoLearn?

Part1

TEACHER:OK,everybody.Let'sgetstarted.Todaywe'regoingtotalkaboutthecriticalperiodinlanguagelearn-ing,ButfirstTdliketoaskyouaquestion:Howmanyofyouhavetriedtolearnanewlanguageasateenagerorasanadule?...Ah,Isee,quiteafewofyou.Well,thenI'msureyouagreethatitsmuchmoredificulttolearnanewlanguagewhenwe'regrownthanitwastolearnyourfirstlanguageasachild,right?Butdoyouknowwhyit's

somuchharder?...Noidea?Well,linguistsbelieveit's

becauseofthecriticalperiodoflanguagedevelopment.

Thecriricalperiodisatheorythatexplainswhyitiseas-ierforchildrentolearnlanguagesthanforadults.That'swhatIdliketodiscusstoday.Butfirst,Idliketostartby

definingthecriticalperiod...andIllgiveyousome

examplesofacriricalperiodinanimals—insongbirds

andcats.ThenI'lltalkabourevidenceforacriticalperiodforlanguagelearninginhumans.

Sowhatexactdlyisacriricalperiod?Theideaofacriricalperiodcomesfromthestudyofanimals.Wesaythattheresacriticalperiod-theonlytime—whentheani-malcanlearnanewskillNow,thecriricalperiodstartsinthefirstweeksormonthsofananimalslife.Duringthistimeitsbrainisreadytolearnnewthings.However,whentheanimalgetsolder,thecriricalperiodends;it

cannotlearnanymore.Sothereareskillsthatmustbe

learnedwhentheanimalisyoung;ifnot,theycantlearn

themasadults.

Now,I'mgoingtomoveontosomeexamples.First,let'stakesongbirds.Asongbirdlearnstosingthefirstfewmonthsafteritsbornbylisteningtoitsparents'songandrepeatingit.Thebirdcanonlylearntodothiswhenit'sababy.Anadultbirdcannotlearntosing.So,ifyouremovethebabybirdfromitsparents—sothatitdoesn'thearthesong—thebirdjustwontlearntosingwhenit'solder.Sothereisaperfectexampleofa

criticalperiod.

Takeanotherexample—cats.Akittenmustlearntouseitscyesinthefirstfewweeksofitslife.Atfirst,thecatcantseeverywell.Butovertime,itbeginstouseitseyes.However,ifyouremoneallthelightintheroomsothecatgrowsupinthedark,itwontbeabletouseitseyes.

Whenthecatisanadult,itwon'tbeabletoseewell.So

thereisanothercriticalperiod—whenacatmustlearn

tosee.

Part2

TEACHER:Nowletslookatthecriricalperiodforlearn-inglanguagesinhumans.Asyou'veprobablynoticed,childrenlearnnewlanguagesmuchmoreeasilyandquicklythanadults.Butwedontreallyknowwhy.

Onetheoryisthatthereisacriticalperiodforlanguage

learning.Thetheoryisthatpeoplesbrainschangewhentheyreadolescentsandthatthesechangesmakeitmoredificultforadultstolearnanewlanguagethanforchil-dren.

Ofcourse,adultscanlearn—manyadultslearntospeakanewlanguage.Theymaynotspeakitperfectly,burtheyspeakitverywell,wellenoughtousethenewlanguagefordailylife.Sowe'tenotlikeadultsongbirds,whocan'teverlearnanewsong.Wecanlearn.

Thatsaid,howevet,thereisevidenceforacriticalperiodforlearningtospeakwithanativeaccmt.Somchowchil-drencanhearthedifferentsoundsbetter,andtheirmouthmusclescanmakethenewsounds.Inmanycases,

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achildwillspeakanewlanguagewithnoforeignaccemtatall.

Butgenerally,adulrswholearnanewlanguageafteradolescencespeakwithaforeignaccemt.Theyneverleamtospeakwithanativeaccent,nomatterhowhardtheytry.Itcanbeveryfrustrating.Wemaybeabletohearthecorrectaccent,butourmourhsjustcantpronouncethesoundscorrectly.Haveyoueverfeltthisway?So,unforru-nately,thisshowsthattheremaybeacriticalperiodwhenhumansmustlearntospeakwithanativeaccent.

Sowecancondludethatthereisacriticalperiodwhen

bothanimalsandhumanscanlearncertainthings.Foranimalslikebirdsandcats,theymustlearntodothingswhentheyarestillveryyoung.Humans,ontheotherhand,canstilllearnsomenewthingsasadults,likelan-

guages,butitsmoredifficult.Adulthumanshavea

criticalperiodforlearningnewaccens.

So,thatsallfornow.Let'sgetintoourdiscussiongroups.Doeseveryonehaveacopyofthehandout?

Unit7AreWeAlone?

Part1

TEACHER:Hello,everyone.Iseveryonehere?Well,let'sgetstarted.Weweretalkinglasttimeaboutthepossibil-iryofotherintelligentlifeintheuniverse.SothatswhereIwanttopickuptoday.Today