1.Itistruethatpeopleofoldtimeshavebuiltmanyoftheworld’sgreatestcitiesonthebanksofariver.Itistruethatmanyoftheworld’sgreatestcitieshavebeenbuiltonthebanksofariver.2.Peoplehaveputbackpartsofstatuestogether.Partsofstatueshavebeenputbacktogether.3.Peoplehavereplacedthemissingpieces.Themissingpieceshavebeenreplaced.mendSomeonehasmendedtheTVset.SomeoneTheTVsethasbeenmendedbysomeone.catch,themouseThemousehasbeencaught.Buy,weddingringTheweddingringhasbeenbought.Theantisepticmaskshavebeenwornduringthewinter.Buy,anewhatAnewhathasbeenbought.save,ThebabyindangerhasbeensavedthebabyindangerhasbeensavedNemoFind,Nemohasbeenfound.ThePresentPerfectPassiveVoicehave/has+been+V(p.p.)1.Theyhavediscussedtheproblemforweeks.Theproblemhasbeendiscussedforweeks.2.Hehasinvitedthefamousscientisttogiveaspeech.Thefamousscientisthasbeeninvitedtogiveaspeech.3.Theyhavespentallthemoney.Themoneyhasallbeenspentbythem.ThePassiveVoice-whentouseit1.动作执行者不易指出或不需明说.Mywatchhasbeenstolen.2.动作执行者不言自明.Iwasaskedseveralquestionsintheoralexam.3.强调动作承受者.Thehousewasburntdown(bytheenemy).Theworkerpaintsthedoor.Theworkerpaintedthedoor.Theworkerwillpaintthedoor.theworker/paint/thedoorThePassiveVoice–howtouseitTheworkerhaspaintedthedoor.Theworkerispaintingthedoor.Theworkerwaspaintingthedoor.Thedoorispaintedbytheworker.Thedoorwaspaintedbytheworker.Thedoorwillbepainted.Thedoorhasbeenpainted.Thedoorisbeingpainted.Thedoorwasbeingpainted.Describethepictures,usingpassivevoice.Thepicturehasbeendrawnbythelittlegirl.Thepictureisbeingpaintedbythelittlegirl.paintpicturebuildcastle18thcenturyThecastlewasbuiltinthe18thcentury.buildnewflyoverseveryyearNewflyoversarebuilteveryyear.TheOlympicGameswillbeheldinBeijingintheyear2008.