Unit3Unit3TheworldofscienceToknowtheuseofpresentprefectpassive.Todosomeexercisesusingthepresentperfectpassive.Toknowsomecareersinscience.現(xiàn)在完成時(have/has+v-ed)

表示說話時已經(jīng)完成的動作，而且這個動作的結(jié)果對現(xiàn)在仍有影響;表示動作發(fā)生在過去，但一直持續(xù)到現(xiàn)在，并且有可能繼續(xù)持續(xù)下去。Doyouknowthestructuresandmeaningsofthepresentperfecttenseandpassivevoice?被動語態(tài)助動詞be+及物動詞的過去分詞be隨主語的人稱、數(shù)和時態(tài)的變化而變化。當(dāng)強(qiáng)調(diào)動作承受者，不必說出執(zhí)行者或含糊不清的執(zhí)行者時，多用被動語態(tài)。PresentperfectpassiveLookatthesentencesfromthereadingpassageandanswerthequestions.aIguessyouhavebeenaskedaboutthetitleofyourbookbefore.bNewinventionslike3Dprintershavebeenusedtomakereplacementheartsandboneparts.1Whathashappenedto“you”insentence(a)?Someonehasasked“you”aboutthetitleofyourbookbefore.aIguessyouhavebeenaskedaboutthetitleofyourbookbefore.bNewinventionslike3Dprintershavebeenusedtomakereplacementheartsandboneparts.2Whohasusednewinventionstomakereplacementheartsandbonepartsinsentence(b)?Peoplehaveused3Dprinterstomakereplacementheartsandboneparts.Comparethemwiththefollowingsentencesandanswerthequestions.cIguesssomeonehasaskedyouaboutthetitleofyourbookbefore.dPeoplehaveusednewinventionslike3Dprinterstomakereplacementheartsandboneparts.3Whatisthedifferencebetweenthetwogroupsofsentences?

Inthefirstgroup,thewordsinredshowtheuseofthepassiveformwiththesubjects,whileinthesecondgroup,thewordsinredshowtheuseoftheactiveformwiththesubjects.4Whydoestheauthorchoosetousethepassiveforminsteadoftheactiveforminthereadingpassage?Theauthorchoosestousethepassiveforminsteadoftheactiveformtoemphasisewhathasbeendone,ratherthanwhoorwhatdoestheaction.Nowlookformoresentenceswiththepresentperfectpassiveinthereadingpassage.1.TheNewAgeofInventionhasjustbeenpublished.2.In

addition,

importantadvanceshavebeenmadeinmedicineandenvironmentalsciencethankstoincreasingcomputerpower.3.Newinventionslike3Dprintershavebeenusedtomakereplacementheartsandboneparts.VerbformActivePassivehave/has+been+v-edHowdoweformthepresentperfectpassivevoice?have/has+v-ed現(xiàn)在完成時的被動語態(tài)意義及結(jié)構(gòu)表示動作發(fā)生在過去,到現(xiàn)在已經(jīng)完成或?qū)ΜF(xiàn)在產(chǎn)生的影響。動詞和被修飾主語構(gòu)成被動關(guān)系?？隙ㄊ剑篽ave/has+been+v-ed否定式：have/has+not+been+v-ed一般疑問句：Have/Has+主語+been+v-ed?特殊疑問句：疑問詞+have/has+been+v-ed?現(xiàn)在完成時的被動語態(tài)有兩種情況：1)表過去開始的被動動作一直持續(xù)到現(xiàn)在，常連用的時間狀語有：for+段時間，since+時間狀語(從句)，thesedays,sofar,uptonow,inthelast/pastfewyears等。如：ThisclasshavebeentaughtbyMr.Brownfortwoyears.HisChinesehasbeenimprovedalotsincehecametoChina.Rowling’snovelshavebeentranslatedintomanyforeignlanguagessofar.2)表某被動動作對現(xiàn)在造成的影響或結(jié)果，常與already,yet,just,ever,never,recently等連用。如：Thebikehasnotbeenrepairedyet.IhavealreadybeenintroducedtoMr.Smith.并不是所有動詞都有被動語態(tài)。happen,takeplace,breakout,belongto,cost,last等不及物動詞或詞組無被動語態(tài)。Greatchangeshavetakenplace

inChinasince1978.【注意】1.現(xiàn)在完成時的被動語態(tài)與一般過去時被動語態(tài)的區(qū)別一般過去時被動語態(tài)表示一個被動的動作發(fā)生在過去，其結(jié)果對現(xiàn)在沒有影響；現(xiàn)在完成時被動語態(tài)的動作或狀態(tài)盡管發(fā)生在過去，但側(cè)重說明該動作或狀態(tài)對現(xiàn)在造成的影響或結(jié)果。Themachinehasbeenrepaired．機(jī)器已經(jīng)修好了。(動作發(fā)生在過去，對現(xiàn)在有影響，修好了。)Themachinewasrepairedyesterday．機(jī)器昨天修了。(只說明動作發(fā)生在昨天。)2.動詞短語是一個不可分割的整體，在被動語態(tài)中要保持其完整性，其中的介詞或副詞不可省略。

e.g.Theorphanshavebeentakengoodcareofhere．孤兒們在這里受到很好的照顧。I.將下面句子中的主動語態(tài)變?yōu)楸粍诱Z態(tài)。

1.NobodyhasheardofSusansinceshemovedtoAmerica.

__________________________________________________2.Theywon'tfinishtheexperimentbeforeteno'clock.___________________________________________________Susanhasn'tbeenheardofsinceshemovedtoAmerica.Theexperimentwon'tbefinishedbeforeteno'clock.3.Wehaven'tgiventhemanythingtoeat.

__________________________________________________4.Haveyoufedthepigsyet?

__________________________________________________5.Wehavealreadydiscussedthisquestion.

__________________________________________________Thisquestionhasalreadybeendiscussed.Theyhaven'tbeengivenanythingtoeat.Havethepigsbeenfedyet?II.用括號內(nèi)動詞的正確形式填空。1.Thesamemistake_______________(make)manytimes.2.Morethan100famousfilms________________(show)inthecitysinceJuly.3.Forhistenthbirthday,Carlwantedabicyclebut________(give)aguitarbyhisparents.4.Althoughit_______________(play)manytimes,hestilllovesit.

5.Threenewschools_______________(open)inourcityinthepast5years.hasbeenmade

havebeenshownwasgivenhasbeenplayedhavebeenopenedRewritetheunderlinedpartsusingthepresentperfectpassive.Withinthenext80years,ourlivesmaybechangedbeyondrecognitionby3Dprinting.Ithasalreadyaffectedmanythingsinourlives,rightdowntothefoodweeat.Forinstance,somerestaurantsinLondonhaveserved3D-printedhamburgerstocustomers.Manythingsinourliveshave3D-printedhamburgershavebeenservedtocustomersinsomerestaurantsinLondon.alreadybeenaffectedButperhapsthemostsignificantsuccessthatpeoplehaveachievedtodateisinmedicine.

Theyhavemadehumanbodyparts,includingabeatingheart,with3Dprintingtechnology.Anditisnotjusthumanswhoarebenefiting-inBrazil,peoplehavegivenanew3D-printedshelltoaturtleinjuredinaforestfire!Butperhapsthemostsignificantsuccessthathasbeenachievedtodateisinmedicine.Humanbodyparts,includingabeatingheart,havebeenmadewith3Dprintingtechnology.Anew3D-printedshellhasbeengiventoaturtleinjuredinaforestfire!3ImagineyouareDrMoore.Lookatthepicturesandtellthepoliceaboutthedamageandlosstoyourlab.Usethepresentperfectpassivewhereappropriate.Thewindowhasbeenbroken.Thelockonthedoorhasbeenbroken.Mytwolaptopshavebeenstolen.Beakersandtesttubeshavebeendestroyed.Thebookcasehasbeenopened,andsomefileshavebeentakenawaywhileothershavebeenthrowneverywhere.Therobothasbeendamaged.thebuildings,destroy,earthquakeThebuildingshavebeendestroyedbytheearthquake.Lookatthepictures,firstlistsomekeywords,andthenmakeupsentencesusingthepresentperfectpassivevoice.machinereplacecomputerThemachinehasbeenreplacedbythecomputer.inourcity,anewbridge,buildAnewbridgehasbeenbuiltinourcity.recently,manytrees,plant,alongtheroadManytreeshavebeenplantedalongtheroadrecently.sevenHarryPorterbooks,J.K.Rowling,sofar,writeSevenHarryPorterbookshavebeenwrittenbyJ.K.Rowlingsofar.CareersinscienceLookatthepicturesandanswerthequestions.physicistmathematician1.Whatdoyouknowaboutthesecareers?Aphysicistisapersonwhodoesresearchconnectedwithphysicsorwhostudiesphysics.Amathematicianisapersonwhoistrainedinthestudyofnumbersandcalculations.geographer

biologistchemistastronomerAchemistisapersonwhodoesresearchconnectedwithchemistryorwhostudieschemistry.Anastronomerisascientistwhostudiesthestars,planets,andothernaturalobjectsinspace.Ageographerisapersonwhostudiesgeographyorisanexpertinit.Abiologistisapersonwhostudiesorworksinthefieldofbiology.2.Whatfamousscientistscanyounameinthesefields?physicistIsaacNewtonAlbertEinsteinmathematicianJohannCarlFriedrichGaussZuChongzhichemistAntoine-LaurentdeLavoisierastronomerEdmondHalleygeographerbiologistAlfredLotharWegenerGregorJohannMendelCompletetheintroductionsaboutdifferentscientistswiththewordsinActivity4.Payattentiontothelanguagethatdescribestheircareers.GuoShoujing(1231-1316)wasafamousChinese___________oftheYuanDynasty.Heinventedtwelvenewinstrumentstostudystarsandplanets.HealsodevelopedacalendarwhichisasaccurateastheGregoriancalendar.AmountainontheMoonandaminor

planetarenamedafterhim.astronomer

British________CharlesDarwin(1809-1882)isbestknownforhisworkOntheoriginofSpecies,inwhichheexplainschangesinspeciesduetonaturalselection.Hisideasdeeplyinfluenceourunderstandingoftherelationshipbetweenhumansandnature.biologistLiDaoyuan(ca466-527)wasafamouswriterand___________oftheNorth