被动语态就是be 动词＋动词的过去分词!像 the cake is bought by him.蛋糕被他买走了.还有些特殊的时候!情态动词后面＋be＋过去分词(pp)1.should be +pp2.must be +pp3.can be +pp另外have/ has/hadhave/has/had +be...