课件英语选择性必修一Unit5Usinglanguage

Unit5RevealingnatureUsinglanguagePastperfectBYMICHELLE①Lookatthesentencesfromthereadingpassageandanswerthequestions.1.Insentence(a),whichactionhappenedfirst,“suspected”or“evolvedfromacommonancestor”?

2.Insentence(b),whichactionhappenedfirst,“refusedtobelieve”or“evolvedfromlowerformsoflife”?3.Whatdoesthestructurehaddoneindicate?Itindicatestheactionhappenedbeforeacertainpastaction.Nowlookformoresentenceswiththepastperfecttenseinthereadingpassage,andsummariseitsuseinyourownwords.1.Itwasayoungmanwhohadleftmedicalschoolwithoutcompletinghisdegree.2....hehadrecentlyreceivedaletterfromhisfatherpredictingthathewouldbe“adisgracetoyourselfandallyourfamily.3.AfterDarwinhadspentsometimeinSouthAmerica,hisroomontheshipwascrowedwithsamplesoftheplantsandanimalshehadcollected.4.Atthattime,peoplebelievedthatallspecieshadappearedonEarthatthesametime,andhadnotchangedsince.5.Itseemedtheirbeakshadevolvedaccordingtowhatfoodwasavailableonthatparticularisland.6.Overtime,ithadslowlyevolvedintomanynewspecies.Grammar:PastPerfectFormsThepastperfectisformedusinghad+pastparticiple.Questionsareindicatedbyinvertingthesubjectandhad.Negativesaremadewithhadnot.Statement:YouhadstudiedEnglishbeforeyoumovedtoNewYork.Question:HadyoustudiedEnglishbeforeyoumovedtoNewYork?Negative:YouhadnotstudiedEnglishbeforeyoumovedtoNewYork.肯定句主语＋had＋过去分词＋其他否定句主语＋had＋not＋过去分词＋其他一般疑问句Had＋主语＋过去分词＋其他？特殊疑问句特殊疑问词＋had＋主语＋过去分词＋其他？SummaryGrammar:PastPerfectUses表示在过去某一时刻或某个动作之前已经发生或完成的动作或存在的状态。这个过去的时刻常用by,before,until等引导的短语或时间状语从句来表示，也可以通过一个表示过去的动作或上下文来表示。Bynineo'clocklastnight,wehadfinishedmostofthework.

Shehadlearntabout500Englishwordsbeforeshewenttomiddleschool.Grammar:PastPerfectUses表示过去某一时间之前发生的动作或存在的状态一直持续到那时，并可能继续下去，常同由for或since引导的表示一段时间的短语或从句连用。Ihadbeenatthebusstopfor30minuteswhenabusfinallycame.Shesaidshehadmadegreatprogresssinceshecamehere.Grammar:PastPerfectUses在含有定语从句的主从复合句中，如果主从复合句叙述的是过去的事，则先发生的动作常用过去完成时。Shereturnedthebookthatshehadborrowed.Thetwins,whohadfinishedtheirhomework,wereallowedtoplaybadmintonontheplayground.Grammar:PastPerfectUses过去完成时常常用在宾语从句(或间接引语)中，这时从句谓语表示的动作发生在主句谓语表示的动作(过去时)之前。IthoughtthatIhadseenhimbefore.Iwassenttothevillagelastmonthtoseehowthedevelopmentplanhadbeencarriedoutinthepasttwoyears.Grammar:PastPerfectUses在含有时间、条件、原因、方式等状语从句的复合句中，若主从句动作的发生有先后顺序，动作在前的要用过去完成时，动作在后的要用一般过去时。Ihadfinishedcookingdinnerbeforeyoucameback.IfoundthelecturehardtofollowbecauseithadstartedwhenIarrived.Grammar:PastPerfectUseswant,hope,mean,plan,intend等动词的过去完成时可以用来表示过去未曾实现的想法、希望、打算或意图，意为“本来……”。Ihadhopedtobebacklastnight,butIdidn'tcatchthetrain.Wehadintendedtocomeandseeyou.Grammar:PastPerfectUses过去完成时常用于某些固定句型：在“hardly...when/nosooner...than/scarcely...when”句型中，主句用过去完成时，从句用一般过去时。Ihadnosoonerreachedhomethanit

begantorain.

＝NosoonerhadIreachedhomethanitbegantorain.

Itwas＋一段时间＋since从句(从句用过去完成时)。

Itwasatleastthreemonths

sinceIhadleftBeijing.

Grammar:PastPerfectUses过去完成时常用于某些固定句型：Itwasthefirst/second/...time＋(that)从句(从句用过去完成时)。ItwasthefirsttimethatIhadchattedonlineinEnglish.

bythetime＋表示过去的从句＋主句(过去完成时)。

BythetimeIgottothestation,thetrainhadalreadygone.

bytheendof＋表示过去的时间＋句子(过去完成时)。

Bytheendoflasttermwehadlearned

10units.

Grammar:PastPerfectUses过去完成时用于虚拟语气中，在wish,asif/asthough,if,ifonly,wouldrathersb.haddonesth.结构或从句中，常用过去完成时来表示与过去事实相反的假设。Ifhehadcaughttheearlybusthismorning,hewouldnothavebeenlateforclass.Iwouldrathershehadn'tdonethat.Grammar:DifferencefromtheSimplePastPerfect过去完成时在时间上强调“过去的过去”，而一般过去时强调过去某一特定的时间。Theyhadarrivedatthestationbytenyesterday.

Theyarrivedatthestationattenyesterday.

在没有明确的表示过去的时间状语作标志时，谓语动词表示的动作发生的时间先后须依据上下文来判断：先发生的用过去完成时，后发生的则用一般过去时。Shewasveryhappyandherwholefamilywerepleasedwithher,too.Shehadjustwonfirstprizeinthecompositioncompetition.

②Completetheparagraphswiththeinformationfromthegivensentences.beganhadledtodevelopedchosetohadmade③Completetheonlineencyclopaediaentrywiththecorrectformofthewordsinthebox.arrivedhadlivedeatenhadintroducedcompeteddeclinedCompetedeclineeatLiveintroducearrive④Workinpairs.Actoutarole-playusingtheinformationinActivity3.OneofyouwillplaythekeeperofLonesomeGeorge,andtheotherwillplaythereporteraskingaboutGeorge.Usethepastperfecttensewhereappropriate.⑤Listentothepodcastandchoosethestatementsthataremade.Biodiversity1Biodiversityisimportant.2Bacteriaarealwaysharmfultohumans.3Somespeciesofbacteriaareusedinfoodproduction.4Manyspeciesofbacteriarecycledeadorganicmatter.5Ourimmunesystemsareabletofightoffallgerms.⑥Listenagainandcompletethefactsheet.madeupofcellsbricksthatareusedtobuildhousesthirtytrillionthirty-ninetrillionhelpwithdigestionbreakdown⑦

Completetheboxeswiththeexpressionsfromthepodcast.Doyouknowabout......?Haveyouheardof......?Bytheway......Actually......Infact,......Speakingofwhich,…CheckingbackgroundknowledgeAddinginformation⑧

Readthepassageandanswerthequestions.Whatspeciesarementionedandwhatisspecialaboutthem?Whatotherunusuallifeformsdoyouknowof?Twospeciesarementioned:thebluewhaleandthewaterbear.ThebluewhaleisthelargestanimalspeciesonEa