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:The baby should be taken good care of by the baby-sitter.2) 有的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。一般变为主语的是间接宾语。例:His mother gave him a present for his birthday. 可改为 He was given a present by his mother for his birthday.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:Someone caught the boy smoking a cigarette. 可改为The boy was caught smoking a cigarette.4)在使役动词have, make, get与感官动词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:Someone saw a stranger walk into the building. 可改为A stranger was seen to walk into the building.5) 有的等于及物动词的动词词组，如动词+介词，动词+副词等，也可以用于被动结构，但要把它们看作一个整体，不可以分开。其中的介词或副词也不可以省略。例The meeting is to be put off till Friday.新初中三年级快扫描二维码关注中考网公众号每天推送学习方法，学科要点帮你迎接2020年中考！