被动语态的构成形式1.被动语态的基本时态变化被动语态通常为十种时态的被动形式,被动语态由be＋过去分词构成,be随时态的变化而变化.以do为例,各种时态的被动语态形式为：1)am/is/are+done(过去分词)一般现在时例Visitorsarerequestednottotouchtheexhibits.2）has/havebeendone现在完成时例Allthepreparationsforthetaskhavebeencompleted,andwe'rereadytostart.3）am/is/arebeingdone现在进行时例Anewcinemaisbeingbuilthere．4）was/weredone一般过去时例IwasgiventenminutestodecidewhetherIshouldrejecttheoffer.5）hadbeendone过去完成时例Bytheendoflastyear,anothernewgymnasiumhadbeencompletedinBeijing.6）was/werebeingdone过去进行时例AmeetingwasbeingheldwhenIwasthere.7）shall/willbedone一般将来时例Hundredsofjobswillbelostifthefactorycloses.8）should/wouldbedone过去将来时例Thenewswouldbesenttothesoldier'smotherassoonasitarrived.9）shall/willhavebeendone将来完成时（少用）例TheprojectwillhavebeencompletedbeforeJuly.10）should/wouldhavebeendone过去将来完成时（少用）例Hetoldmethathisnewclotheswouldhavebeenmadeverysoon.2.被动语态的特殊结构形式1)带情态动词的被动结构.其形式为：情态动词＋be＋过去分词.例Thebabyshouldbetakengoodcareofbythebaby-sitter.2)有些动词可以有两个宾语,在用于被动结构时,可以把主动结构中的一个宾语变为主语,另一宾语仍然保留在谓语后面.通常变为主语的是间接宾语.例Hismothergavehimapresentforhisbirthday.可改为Hewasgivenapresentbyhismotherforhisbirthday.3)当“动词+宾语+宾语补足语”结构变为被动语态时,将宾语变为被动结构中的主语,其余不动.例Someonecaughttheboysmokingacigarette.可改为Theboywascaughtsmokingacigarette.4）在使役动词have,make,get以及感官动词see,watch,notice,hear,feel,observe等后面不定式作宾语补语时,在主动结构中不定式to要省略,但变为被动结构时,要加to.例Someonesawastrangerwalkintothebuilding.可改为Astrangerwasseentowalkintothebuilding.