Unit+5+A+delicate+World+Starting+out+ Understanding+ideas+課件【知識精講精研】高二英語外研版（2019）選擇性必修第二冊

Unit5Period1Startingout&Understandingideas課堂學(xué)習(xí)Watchthevideoandanswerthequestions.1ArehumanspartofEarth'secosystems?Why?2Inwhatwayscanhumansaffectecosystems?1Startingout1ArehumanspartofEarth'secosystems?Why?2Inwhatwayscanhumansaffectecosystems?Yes.HumansarepartofEarth'secosystems.Becauseallthelivingthingsliveinecosystemsandpeoplearelivingthings.Humanscanaffectecosystemsinpositiveandnegativeways.Forexample,tohaveapositiveinfluenceonecosystems,peoplecanplanttrees,feedandprotectanimals,recyclethings,etc.However,deforestation,airandwaterpollutionandexcessivewasteaffectecosystemsinanegativeway.2Whatdoyouthinkalatersatelliteimagewouldshow?3Whatdoyouthinkcausedthesechanges?Lookatthesatelliteimagesandanswerthequestions.21Whatishappeningtotheareaaccordingtothesatelliteimages?AralSeaisbecomingsmallerandsmaller/shrinking.Thewaterareawillbesmaller.Maybeit'sduetooverexploitation.1Lookatthepictureandanswerthequestions.Understandingideas1Whatanimalscanyouseeinthepicture?2Whatkindofchangeswouldtakeplace

ifcats,ratsandrabbitswereintroduced

toanenvironmentlikethis?Penguinsandabird.Theywouldhuntthebirdsandeatthenativevegetation,thusupsettingthelocalecologicalbalance.MACQUARIEISLAND:fromChaostoConservation1

IamstandingonMacquarieIsland,intheSouth-westPacificOcean,halfwaybetweenAustraliaandAntarctica.Strongwindsandstormyseashavehelpedsculptitslong,thinshape.Thegreengrassandbarerockofitslandscapecontrastdramatically,givingitawildandnaturalbeauty.NovisitorwouldthinkitsurprisingthattheislandisaUNESCOWorldHeritageSite.Norwouldtheyfailtoimaginehowitsnativeinhabitants,includingroyalpenguins,kingpenguins,andelephantseals,existedinperfectharmonywiththeirnaturalhabitatforthousandsofyears.2

Buttheisland'smorerecenthistorytellsadifferentstory.It'satragicstorythatbeganin1810whenhumansarrivedontheisland.Intheirshipstheyunknowinglybroughtratsandmice.Thesesmallanimalsquicklytookovertheisland,eatingthebirds'eggsandattackingbabybirds.Catswerebroughttotheislandtocontroltheratsandmice.Unfortunately,thecatssubsequentlydevelopedanappetiteforthebirds,too.3Meanwhile,rabbitswereintroducedtotheislandasasourceoffoodforhumans.Looseontheisland,theydidwhatrabbitsdobest-theymultipliedrapidlyandbeganeatingthenativevegetationanddiggingholes,whichcausedsoilerosion.Theexplodingrabbitpopulationprovidedplentifulfoodforthecats,meaningthatthenumberofcatsalsoincreased.Thisinturnledtomorecatshuntingthebirds.Theendresultwasthatparakeets,oncelargeinnumberandnativetotheisland,diedoutin1891.4

EvenafterMacquarieIslandbecameanofficialnaturereserveinthe1970s,therabbitsremainedoutofcontrol.Expertsfeltitnecessarytocomeupwithaplantoremovealltherabbitsfromtheisland.Withthisgoalinmind,aviruswasreleasedontotheisland.Butalthoughtheviruscausedtherabbitpopulationtodecreasefrom130,000toaround10,000,italsomeantlessfoodforthecats.Thecatsinconsequenceturnedtheirattention-andtheirstomachs-backtothenativebirds,killingupto60,000eachyear.Inthe1980s,trapsanddogswereusedtocatchthecats.ThelastMacquarieIslandcatwascaughtin2000.5Butasthesayinggoes,“Whilethecat'saway,themicewillplay."Withthedepartureofthecatsfromtheisland,themouseandratpopulationstartedtoincrease.Andrememberthose10,000orsorabbits?Itturnedoutthattheydevelopedanimmunitytothevirus,andtheirnumbersexplodedonceagain.Then,in2006,therabbits'diggingcausedsomelandtocollapse,andkilledasubstantialnumberofpenguins.Thisincidentmadeitclearthattherat,mouseandrabbitproblemneededsolvingonceandforall.6

So,IamhereonMacquarieIslandtoparticipateintheprogrammetotacklethisveryproblem.Thefirststepinvolvedpoisonbeingdroppedfromhelicopters.Thenextstepistoremovethelastremaininginvadingspecies,andthat'swhereIcomein-withmydogs.Theyhavebeentrainedtofindeverylastone,withoutharmingthenativeanimals.Thisinterventionisalong,much-delayedendingtoasadstory,butwehumansoweittotheislandtogiveitahappyending.

Postscript:In2014,MacquarieIslandwasdeclaredpest-freeandtheisland'secologyisfinallyontheroadtorecovery.Non-nativespeciesintroducedtoMacquarieIslandattackednativebirds,andledtoasubstantialreductionofbirdpopulationandeventheextinctionofparakeets.Inaddition,non-nativespeciesateanddevastatedthenativevegetation.Allofthisplayedapartinupsettingthenaturalharmonyoftheisland.Butnowtheisland'secologyisontheroadtorecoverywithhumanefforts.Skimming2ReadthepassageandfindoutwhathappenedtoMacquarieIsland.Lookthroughthepassage,divideitintoparts,andgetthemainideaofeachpart.Part1Para.1ThelocationandnaturalcharacteristicsofMacquarieIslandPart2Para.2-Para.5ThetragedystoryofMacquarieIslandPart3Para.6WhattheauthorisdoingnowtoMacquarieIslandScanningChoosetheauthor'spurposeinwritingthepassageandgiveyourreasons.3Carefulreading1ToanalysehowMacquarieIslandwassavedfromdestruction.2ToinformreadersofthechaoscausedonMacquarieIslandbyhumans.3ToentertainreaderswithafunnystoryaboutwhathappenedonMacquarieIsland.4Tosuggestwaysinwhichanecosystemcanbeprotected.Organiseinformationfromthepassageandcompletetheflowchart.4Answers:ACTION(S)Catswerebroughttotheisland.Rabbitswereintroducedtotheisland.Aviruswasreleasedontotheisland.Trapsanddogswereused.Poisonanddogswereused.PURPOSE(S)Toprovidefoodforhumans.Toremovealltherabbitsfromtheisland.Tocatchthecats.Toremovealltheremaininginvadingspecies.→→→→RESULT(S)theytookovertheisland,eatingthebirds'eggsandattackingbabybirdsThecatsdevelopedanappetiteforthebirds.theexplodingrabbitpopulationprovidedplentifulfoodforthecats.Thisledtomorecatshuntingthebirds.Asaresult,parakeetsdiedoutin1891.Substantialreductionofrabbitpopulationledtocatskillingmorenativebirds.Thedepartureofthecatsresultedinanincreasingpopulationofratsandmice.Andtherabbitpopulationexplodedonceagain.Theislandwaspest-freeanditsecologyisontheroadtorecovery.→→→→→→NowtalkabouthowhumaninterferenceledtosuchsevereconsequencesforMacquarieIsland.1.In1810,humanarrivedontheisland.However,ratsandmicewerebroughttherebyaccident,andtheytookovertheisland,eatingthebirds’eggsandattackingbabybirds.2.Then,catswerebroughttotheisland.Butthecatsdevelopedanappetiteforthebirds.3.Rabbitswereintroducedtotheisland.Rabbitsmultipliedandcausedsoilerosion.Theexplodingrabbitpopulationprovidedfoodforthecats.Thisledtomorecatshuntingthebirds.Asaresult,parakeetsdiedoutin1891.4.Aviruswasreleasedontotheislandtoremovealltherabbitsfromtheisland.Substantialreductionofrabbitpopulationledtocatskillingmorenativebirds.5.Trapsanddogswerebroughttotheislandtocatchthecats.Thedepartureofcatsresultedinanincreasingpopulationofratsandmice.Andtherabbitpopulationexplodedonceagain.Then,in2006,therabbits'diggingcausedsomelandtocollapse,andkilledasubstantialnumberofpenguins.1Whatisyourunderstandingof“...wehumansoweittotheislandtogiveitahappyending”?2Doyouthinkitwasrighttoeradicatethe“pests”

fromMacquarieIsland?Giveyourreasons.3Howcouldsimilarsituationsbeavoidedinthefuture?4Whatlanguagecanyouusetotalkaboutcauseandeffect?Howwouldyouapplyittoyourreadingandwriting?Think&Share1Whatisyourunderstandingof“...wehumansoweittotheislandtogiveitahappyending”?2Doyouthinkitwasrighttoeradicatethe“pests”fromMacquarieIsland?Giveyourreasons.3Howcouldsimilarsituationsbeavoidedinthefuture?4Whatlanguagecanyouusetotalkaboutcauseandeffect?Howwouldyouapplyittoyourreadingandwriting?Yes.The“pests”inthesentencereferstotheinvadingspecies.Torestoretheecologicalbalance,itwasobviousthathumansmusteradicatethe“pests”.Itwashumansthatbroughtinvadingspeciestotheisland,breakingthebalanceoftheisland’snature.Soitisourdutytohelpitreturntonormal.Toavoidsimilarsituationsinthefuture,weshouldprotectthenaturalecosystemandbeawareofthepotentialimpactthathumanactivitiescanhaveonecosystems.1.MACQUARIEISLAND:fromChaostoConservation麥夸里島：從混亂到保護(hù)

chaosn.[U]大混亂；紊亂causechaos導(dǎo)致混亂inchaos處于混亂之中economic/political/domesticchaos經(jīng)濟(jì)/政治/國內(nèi)的混亂chaoticadj.混亂的；混沌的Languagepoints2.Thegreengrassandbarerockofitslandscapecontrastdramatically,

givingitawildandnaturalbeauty.

綠色的草地和光禿禿的巖石

景觀形成了鮮明的對比，賦予了它一種野性和自然的美。

“giving...beauty”為現(xiàn)在分詞短語作結(jié)果狀語。3.NovisitorwouldthinkitsurprisingthattheislandisaUNESCOWorldHeritageSite.沒有游客會對該島被聯(lián)合國教科文組織列為世界遺產(chǎn)感到驚訝。

本句為主從復(fù)合句。其中it作形式賓語，that引導(dǎo)賓語從句。4.Norwouldtheyfailtoimaginehowitsnativeinhabitants,includingroyalpenguins,kingpenguins,andelephantseals,existedinperfectharmonywiththeirnaturalhabitatforthousandsofyears.他們也不難想象出，數(shù)千年來，包括帝企鵝、王企鵝和象海豹在內(nèi)的當(dāng)?shù)貏游锸侨绾闻c其自然棲息地完美地和諧共存的。

(1)nor為否定詞，可以用在一個否定句之后來引出另一個相關(guān)的否定句，在這種情況下，它所引導(dǎo)的句子需要用倒裝語序，常用結(jié)構(gòu)為：

“nor+助動詞/情態(tài)動詞+主語+謂語動詞+其他成分。

e.g.Hedidn'tquithisjob,norwashefired.

他沒有辭職，也沒有被解雇。

(2)failtodosth.意為“未能做成某事”，表示否定概念，

和否定詞連用時表示肯定概念。

e.g.Thegreatbridgecannotfailtostopyouinyourtracks.

這座宏偉的大橋一定會讓你止步觀賞。拓展：failinsth./doingsth.做某事失??；沒能做到某事

e.g.Hefailedinpersuadinghertogotherewithhim.

他沒能說服她和自己一起去。

(3)how引導(dǎo)賓語從句，作imagine的賓語。5.It'satragicstorythatbeganin1810whenhumansarrivedontheisland.這個悲慘的故事始于1810年人類來到島上。

本句中的It指的是前面的adifferentstory。that在此引導(dǎo)定語從句，修飾先行詞atragicstory；該定語從句中包含一個when引導(dǎo)的定語從句，修飾1810，when在此定語從句中作時間狀語。6.Thesesmallanimalsquicklytookovertheisland,eatingthebirds'eggsandattackingbabybirds.這些小動物很快占領(lǐng)了島嶼，吃鳥蛋并攻擊幼鳥。此處的“eatingthebirds'eggs”和“attackingbabybirds”是and連接的兩個并列的v.-ing短語，在句中作伴隨狀語。7.Catswerebroughttotheislandtocontroltheratsandmice.貓被帶到島上來控制老鼠。“tocontroltheratsandmice”為動詞不定式短語作目的狀語。8.Unfortunately,thecatssubsequentlydevelopedanappetiteforthebirds,too.不幸的是，這些貓后來也對這些鳥產(chǎn)生了食欲。

appetiten.[U·C,usuallysing]食欲，胃口[c]強(qiáng)烈欲望developanappetitefor...對……產(chǎn)生食欲haveagood/poor/noappetite胃口好/胃口不好/沒有胃口haveanappetitefor...渴望……(appetite前可用形容詞修飾)9.Meanwhile,rabbitswereintroducedtotheislandasasourceoffoodfor

humans.與此同時，兔子被引入島上作為人類的食物來源。

introduce...to/into...把……引入……introduce...tosb.向某人介紹……introduceoneself自我介紹introductionn.介紹；引進(jìn)；序言10.Looseontheisland,theydidwhatrabbitsdobest

-theymultipliedrapidlyandbeganeatingthenativevegetationanddiggingholes,whichcausedsoilerosion.放任其在島上的情況下，它們做了兔子最擅長的事情——它們迅速繁殖，并開始吃當(dāng)?shù)氐闹脖缓屯诙?，這導(dǎo)致了土壤侵蝕。what引導(dǎo)賓語從句；破折號后解釋的是whatrabbitsdobest的內(nèi)容。which引導(dǎo)非限制性定語從句，修飾整個主句。11.Theexplodingrabbitpopulationprovidedplentifulfoodforthecats,meaningthatthenumberofcatsalsoincreased.兔子數(shù)量的激增為貓?zhí)峁┝顺渥愕氖澄?，這意味著貓的數(shù)量也在增加。

“meaning...increased”為現(xiàn)在分詞結(jié)構(gòu)作結(jié)果狀語；

that引導(dǎo)賓語從句。12.Thisinturnledtomorecatshuntingthebirds.這反過來又導(dǎo)致更多的貓捕獵這些鳥。

inturn反過來；繼而，轉(zhuǎn)而；輪流，依次

leadto導(dǎo)致；通向

e.g.Increasedproductionwill,inturn,leadtoincreasedprofits.增加生產(chǎn)會繼而增加利潤。13.Theendresultwasthatparakeets,oncelargeinnumberandnativetotheisland,diedoutin1891.最終的結(jié)果是，曾經(jīng)數(shù)量龐大、原產(chǎn)于該島的長尾小鸚鵡在1891年滅絕了。

(1)“thatparakeets....in1891”為that引導(dǎo)的表語從句。

(2)(be)nativeto原產(chǎn)自……e.g.TheseelephantsarenativetoAfrica.這些大象原產(chǎn)于非洲。

(3)dieout消亡；滅絕e.g.Howdidthedinosaursdieout?恐龍是如何滅絕的？14.EvenafterMacquarieIslandbecameanofficialnaturereserveinthe1970s,therabbitsremainedoutofcontrol.即使在20世紀(jì)70年代麥夸里島成為官方自然保護(hù)區(qū)后，兔子仍然無法控制。(1)after引導(dǎo)時間狀語從句。

(2)outofcontrol失去控制

e.g.Pricesarespirallingoutofcontrol.物價飛漲，失去控制。15.Expertsfeltitnecessarytocomeupwithaplantoremovealltherabbitsfromtheisland.

專家們認(rèn)為有必要制定一個計劃，把所有的兔子從島上趕走。

“feltitnecessary”構(gòu)成動詞+it(“it”作形式賓語)+adj(作賓語補(bǔ)足語)，“tocomeupwithaplan”不定式短語為真正賓語后置；“toremovealltherabbitsfromtheisland”為不定式短語作后置定語，修飾aplan。16.Withthisgoalinmind,aviruswasreleasedontotheisland.懷著這個目標(biāo)，一種病毒被釋放到島上。

此處屬于with復(fù)合結(jié)構(gòu)，介詞短語inmind作賓補(bǔ)，該結(jié)構(gòu)在句中作狀語。17.Butalthoughtheviruscausedtherabbitpopulationtodecreasefrom130,000toaround10,000,italsomeantlessfoodforthecats.

但是，盡管病毒導(dǎo)致兔子數(shù)量從13萬只下降到大約1萬只，這也意味著貓的食物減少了。(1)although引導(dǎo)讓步狀語從句。

(2)

decreasev.（使）變小，（使）減少n.減少，減少的量decreaseby...減少了……（表示減少的量）decrease(from.…)to…(從……)減少到……（表示減少后的量）decreasein...在……方面減少adecreasein...在……方面減少onthedecrease在減少聯(lián)想拓展：increasev.&n.增加，增長increaseto...增加到……（表示增加的結(jié)果）increaseby...增加了……（表示增加的幅度）increasein...在……方面增加ontheincrease在增加18.Thecatsinconsequenceturnedtheirattention-andtheirstomachs-backtothenativebirds,killingupto60,000eachyear.結(jié)果，這些貓把注意力——以及它們的胃——轉(zhuǎn)移到了本土鳥類身上，每年殺死多達(dá)6萬只鳥。

(1)inconsequence結(jié)果；因此

e.g.Inconsequence,retailsalesinArocaCityareboundtoincreasesubstantially.因此，ArocaCity的零售額必然會大幅增長。(2)“killing...year”為現(xiàn)在分詞短語作結(jié)果狀語。19.Inthe1980s,trapsanddogswereusedtocatchthecats.20世紀(jì)80年代，人們用陷阱和狗來抓貓。

trapn.夾子；陷阱；圈套；困境

vt.(trapped,trapped)困?。皇瓜萑肴μ譩etrappedin被困在……；陷入……中

=becaughtin=bestuckintrapsb.into(doing)sth.誘使某人做某事lay/setatrap(forsb./sth.)(給某人某物)設(shè)下圈套fall/walkintoatrap落入圈套20.Butasthesayinggoes,“Whilethecat'saway,themicewillplay."但正如俗語所說，“山中無老虎，猴子稱大王”。

as引導(dǎo)非限制性定語從句。21.Andrememberthose10,000orsorabbits?

還記得那一萬只左右的兔子嗎？

orso大約，左右e.g.Wewanderedaboutthetownforanhourorso.我們在城里到處游逛了一個小時左右。22.Itturnedoutthattheydevelopedanimmunitytothevirus,andtheirnumbersexplodedonceagain.

事實證明，它們對病毒產(chǎn)生了免疫力，它們的數(shù)量再次激增。

(1)本句為主從復(fù)合句。其中It作形式主語，that引導(dǎo)主語從句。(2)turnout結(jié)果是，證明是；（大量）出席，參加；制造，生產(chǎn)turnout(tobe)...結(jié)果（是）……Itturnsoutthat...結(jié)果……23.Thisincidentmadeitclearthattherat,mouseandrabbitproblemneededsolvingonceandforall.這件事清楚地表明，老鼠和兔子的問題需要一勞永逸地解決。

(1)本句為主從復(fù)合句。其中it作形式賓語，th