被动语态的特殊用法

⑴双宾语的被动语态：
①含有双宾语的主动变为被动语态时，一般变间接宾语（sb.）为被动语态的主语，直接宾语的位置不变；
②也可变直接宾语为被动语态的主语，间接宾语的位置不变，但一般要在其前面加上介词to/for。如：Mr. Smith bought Jim a new bike. →Jim was bought a new bike by Mr. Smith. →A new bike was bought for Jim by Mr. Smith.
⑵复合宾语的被动语态：
①含有复合宾语的主动语态变为被动语态时，宾语补足语的位置不变；
②如果宾语补足语是不带to的动词不定式，变成被动语态时，应加上to。如：How did you make the baby stop crying? →How was the baby made to stop crying?
⑶短语动词的被动语态：短语动词在变为被动语态时，注意末尾的介词或副词不能省略。如：We must take care of old people. →Old people must be taken care of (by us).