1、 主动句为SVO结构，将主动句宾语变成被动句的主语，将随后的主动态动词词组变成被动态的词组，将原本主语放在随后的by-词组中，如果不突出动作执行者，可省去by-词组。 :They published the criminal. = The criminal was published.
2、主动句带有情态助动词或半助动词，变成被动句时，情态助动词或者半助动词褒词不变，随后不定式由主动态变成被动态。 He is likely to let you down =you are likely to be let down. They should do the work at once. =the work should be done at once
3、当SCVoO结构变成被动句时，Father gave me(间) a watch（直）. a 以间接宾语为被动句主语。I was given a watch. b 以直接宾语为被动句主语。 A watch was given to me.（当间接宾语作为保留宾语后置时，其前必须带介词） 当一个宾语变成被动句的主语时，另一个宾语变成了“保留宾语”
4、结构为SVOC，将原本宾语变成主语，动词主动态变成被动态，原本的宾语宾语补语变成主语补语 We have painted the window white =The window have been printed white
5、by-词组的运用取决句子是否要突出动作执行者 The picture was printed by （a very good friend of mine who i like you to meet somtimes）主语过长，避免头重脚轻
6、并非所以主动句和被动句都可以转化 ： aown 和have 都可以表所有关系但是own 可以在被动句里表现但 have不可以。the house was had by Bob.错误 b一些类似have（有）的静态动词也没有被动态 比如 become（适合）hold （能容纳）resemble（像）；一些主动句的宾语为反身代词或相互代词的时候也没有被动态 c少数动词只以被动态出现 was born ；is reputed
