學必求其心得，業必貴于專精學必求其心得，業必貴于專精學必求其心得，業必貴于專精教材習題點撥COMPREHENDINGAnswerkeyforExercise1：Paragraph1：AwidelyacceptedtheoryabouttheformationoftheuniverseParagraph2:TheformationoftheearthParagraph3：TheimportanceofwaterforlifeParagraph4:ThedevelopmentofplantsandanimalsontheearthParagraph5：ThearrivalofhumansandtheirimpactontheearthAnswerkeyforExercise2：107384961521211AnswerkeyforExercise3：1Becausethewaterremainedontheearth.2Becauseplantsprovideoxygenforanimalstobreathe.3Becausedinosaursdiedoutlongbeforehumanbeingsdevelopedontheearth。4ThenameisPluto.Scientistsnowthinkitistoosmalltobecalledaplanet.5Humanbeingscausedglobalwarming。SuggestedanswerstoExercise4：Discoursemarkers:however，afterthat,next，later,finally，thus，asaresultofSentenceconnectorsorconjunctions:and，but,becauseSuggestedanswerstoExercise5:Theotherpuzzleshiddeninthepassageare:Howdidtheearth’satmospheredevelop?Whydidwaterstayontheearthbutnotontheotherplanets？Howdidlifeformsdevelop?Whydidsomelifeformsdisappear？LEARNINGABOUTLANGUAGEDiscoveringusefulwordsandexpressionsAnswerkeyforExercise1：-(en)ceun。presentviolentconfidentdifferentpatientpresenceviolenceconfidencedifferencepatiencecertainfairpaidlikekinduncertainunfairunpaidunlikeunkind-al-istcultureglobeuniverseagriculturemathematicsculturalglobaluniversalagriculturalmathematicalartphysicschemistrybiologyscienceartistphysicistchemistbiologistscientistAnswerkeyforExercise2：1C2A3C4BAnswerkeyforExercise3:fundamental，astronomy，gavebirthto，existed,Asaresult，atoms，prevents...from,puzzleEmotionalwordsCalmwordsviolentangryrudeshockedexcitedcrazypatientgentlerelaxingkindeasy.goingcalmDiscoveringusefulstructuresAnswerkeyforExercise2：1Whathasnotyetbeenprovedishisdiscovery.2Whethertheotherastronomersaccepthisideasremainsaquestion。3Howlifefirstappearedonearthisstillamysterytoscientists。4Whytheearthisbecomingwarmerisanimportanttopicforresearch.5ItamazedeverybodythatStephenHawkingat65experiencedzerogravityduringaflight.6ItisasurprisethatPlutoisnolongerconsideredaplanetinoursolarsystem。SuggestedanswerstoExercise3：1,4，3,5，2，6USINGLANGUAGEListeninganddiscussingLISTENINGTEXTTHEORIESOFGRAVITYMichaelJonesoftheNewSpaceMagazineistalkingwithspacetravellerLiYanpingaboutchangesinthetheoryofgravity。LY＝DrLiYanpingMJ＝DrMichaelJonesPart1MJ：Hello，DrLiYanping。It’ssogoodofyoutotalktome。Somestudentsaskuswhythingsalwaysfallbacktoearthifyouthrowthemupintheair。Couldyouexplainit？LY：Well，atfirstpeoplethoughtitwasbecausetheearthwasthecentreoftheuniverse。Ofcoursethatwaswrong.OnedayIsaacNewtonwatchedanapplefalltotheground。Hesaidthatsomethingelsemustbepullingtheapplebacktoearth。Hecalledit“gravity”．MJ:Isee.Didpeopleaccepthisidea？LY：Theydid.Latertheyworkedoutthatbiggerobjects(likethesun)havestrongergravitythansmallerobjects（likeourplanets)．Ifyou'retravellingindeepspace，youcouldn'tfallbacktotheearth.You'rejusttoofaraway.Part2MJ：Doesitmeanthere’snogravityinspace？LY：No。Inaspaceshipyouwouldfeelthepullasitgotclosertosuchanobject。Youwouldtravelfasterandfastertowardsit.MJ：Untilyouhitit？LY：Notexactly.Youmaypassitveryfastandthenitwouldthrowyououtintospaceagain。Afterthatyouwouldslowdowntotheusualspeed。MJ：Howdoyouknowthis?LY：In1905Einsteinsaidthatinspacelargeobjectsmakespace。timebend；thelargertheobject，thefurtherspace-timebends。Sotimegoesslowerinverystronggravity。MJ：Whataboutblackholes？LY：That'saplaceinspacewhichhassuchastrongmassthatnothingcanescapefromitsgravity。Thereisakindofedgearoundthismass.Ifyoucrossoverthisedge，it’simpossibleforyoutogetback.Howeverifyoudon'tcrossthisedge，youcanstillescape.StephenHawkinghasdonealotofresearchintoblackholes。Hehasshownthatthey“spit”thingsoutaswellas“eat”them。AnswerkeyforExercise2：SummaryBiscorrectbecauseitgivesaclearideaofwhatthelisteningpassageisabout.SummaryAisnottrue。Thethreescientistswantedtoexplainhowtheuniverseworkedandnothowitbegan.SummaryCistoogeneralanddoesnotgiveenoughdetailaboutwhatthelisteningpassageisabout。AnswerkeyforExercise3：IsaacNewtonAlbertEinsteinStephenHawkingIdeaLargebodieshaveaforcewhichpullsthingstowardsthem.Inspacelargeobjectsmakespaceandtimebend；thelargertheobject，thefurtherspaceandtimebend。Blackholeshaveaverylargemassandpullthingstowardsthem.DevelopmentThebiggertheobjectthestrongerthegravity.Timegoesslowerinverystronggravity。Ifyougoovertheedge，youcannotgetout；butifyoudonot，youmaybeabletoescape。ReadingAnswerkey：1Thepullofgravitybecameverystrongashelefttheearth'satmosphere.Hisweightisnormal。2Itdisappearedwhenhewasinspace.Heisweightless。3Itwasverylightwhenhewasonthemoon。Heweighslessthanonearth.Speakingandwritingtoprotectyourskin:aspacesuitthatcansupplyyouwithwarmwaterifit’stoocoldonthemoonandcoolwaterifthetemperatureistoohot.tostopyouflyingoffintospace：aropetotieyoutothespaceshiptostopyourfoodfloatingaway:liquidspacefoodthatyoucankeepinatubeandeatwithastraw(練習冊教學指導）LISTENINGLISTENINGTEXTANINTERVIEWWITHYANGLIWEIR＝MrRenaultY＝YangLiweiPart1R：Thankyousomuch，MrYang，forcomingtotalktoustodayaboutyourexperienceinspace.Y:Notatall.I'mhappytobehere.R:Pleasecanyoutellusyourmostexcitingmoment?Y:Well,thatwaswhenthespaceshipbegantoliftofftheground。ThenIknewthatIwasreallyonmywayandthatChinawouldbecomethethirdcountrytosendpeopleintospace.R：Didyoufeelafraid？Y：No，becauseIwastrainednottoworry.SoIwatchedallmyinstrumentsandstayedcalm.R：Whatsurprisedyou？Y：Thebeautyofspace.I’dneverrealizedhowlovelytheearthlookstillIwasgoingroundit.Part2R：Didyoualwayswanttobeanastronaut？Y：Well，IdreamedofitwhenIwasyoung，butIneverthoughtmywishwouldcometrue。Itallhappenedgradually.FirstIgotmydegreeandthenItrainedfortenyearstoflyairplanesandthentoflyaspaceship。R：Isee。Didyouhavetobeacertainsizeandweight?Y:Yes。Anastronauthastobesmallerthan170cmandweighlessthan70kg.R：Soyouweretheperfectchoice！Butofcourseyouhadtoworkveryhard.Wouldyouliketogointospaceagain?Y：Yes,Iwouldiftherewasanopportunity。I'dlovetogotothemoononeday。R：Ihopewe’llbetalkingtoyouagainafteryou’vefinishedthattrip！Goodbye，MrYang.Thankyoufortalkingtous.Y：Itwasmypleasure。AnswerkeyforExercise1:1Severalcountriesareinvolvedinspacetravelwithsatellitesandspaceshipsthathavevisitedoneoftheplanets（Mars：USA）andthemoon（USA)．Onlyonecountryhassentastronautstothemoonandreturnedthemsafely—theUSA.2Threecountrieshavesentastronautsintospace：Russia，USAandChina.3TheRussianastronautshavetravelledroundtheearthandlivedinaspacestation.TheAmericanastronautshavetravelledroundtheearth，livedinaspacestationandlandedonthemoon。TheChineseastronautshavetravelledroundtheearthandonehaswalkedinspace。AnswerkeyforExercise2:Themainideaistheexcitementofspacetravelandthequalificationsandexperienceneededtobecomeanastronaut.AnswerkeyforExercise3：QuestionsYangLiwei’sanswersWhenwasthemostexcitingmoment?Whenhisspaceshipliftedoffthegroundheknewhewasreallyonhiswayintospace。Whatsurprisedhim？Thebeautyofspace.Whatdidhedo？Hewatchedallhisinstrumentsandstayedcalm。AnswerkeyforExercise4：InformationonYangLiwei，theastronautEducationHegothisdegree。TrainingHetrainedfortenyearstoflyairplanesandthentoflyaspaceship。PhysicalqualitiesSmallerthan170cm；lessthan70kg。PersonalqualitiesCalm，hard.working.AnswerkeyforExercise5：dreamed，young,wish，true,gradually,opportunity，loveUSINGWORDSANDEXPRESSIONSAnswerkeyforExercise1：1blockingout2brokeout3gaveout4soldout5watchout6hangoutAnswerkeyforExercise2：1religions，religious2like，unlike3gentle，gently4presentation，presentAnswerkeyforExercise3：1Nowthatwehavefinishedthedesign，thecompany,initsturn，willdotheconstruction.2Thefiredidnotcausetoomuchdamage，becausethefirefightersarrivedintime.3Thespaceshipwaspulledclosetothesatellitebyitsstronggravity。4Thesandstormledtoachainreactionwhichendedinaserioustraincrash。5Theatmosphereintheclassroomrelaxedaftertheteacher’shumoroustalkcheeredusup.6Don'tdisturbher。Shegavebirthtoaboylastnightandnowsheisasleep。7Mostoftheevidenceisdestroyed。Thus，it’simpossibletoprovethatthedrugisharmful。8Cloudsaremassesofverysmalldropsofwaterthatfloatinthesky。AnswerkeyforExercise4：existed，lived，developed，protect.。。from，climate，multiplied，weather,prevent。。。fromUSINGSTRUCTURESAnswerkeyforExercise1：6，2，7,3，1,5,46scientists’belief7HissuggestionSuggestedanswerstoExercise2:1Whatinterestsmemostinthisunitisastronomy。2Whenthepartywillbeheldhasn'tbeendecidedyet。3Whetherwevisitthezoothisweekenddependsonyourbehaviour.4Howyouplanyourweddingisapersonaldecision.5Whythegatewasunlockedwhenwecamehomeisapuzzletous。6Itisfunnythatyouhavenotreceivedtheinvitationtothepartyyet.7Itworriedusthatmanypeoplewhoridebicyclesdonotlookwheretheyaregoing。8Itappearsthatthecomputercoursewillnotstarttillnextweek.LISTENINGTASKLISTENINGTEXTANINTERVIEWWITHLIYANPINGW＝WallisL＝LiYanpingW：MrLi，wouldyoupleasetellusaboutyourspacewalk？L:Yes.I’dbehappyto。WecleanedandrepairedtheHubbletelescope。W：Oh,andisthatwhenyoudidyourspacewalk？L：Yes.W:Howdidyouprepareforit?L：Firstwehadtogetintospacesuits.They'reverythickandcarryalltheoxygenweneedtobreathe。Thesuitalsohashotandcoldwatersoitcanwarmusifit'stoocoldorcoolusifit'stoohot。Soit’sveryheavy。W：Isitdangeroustoleavethespaceship？L：Yes，indeed。Whenweleave，wegointoasmallroom。Wehavetoweargravitybootstowalkthere.Weclosethedoorbehindusandthenweopenthedoortospace.Thenourgravitybootsstopworkingandweflyoutofthedoor.W:Howdoyoumoveaboutinspace?L:Weusesmallenginestomovearound.Togoleftwepushtherightengineandtogorightwepushtheleftone。Wemoveslowlybecausewedon'tweighanything.Wecanflyaroundlikefeathers.W：Whatdoesitfeellikeinspace？L：Verystrange.Thereisnogravitysodoinganyjobisverytiring。W：Whathappensifyouflytoofarfromthespaceship?L：You’dnevergetbacksowetieourselvestothespaceshipwithaspeci