is your classroom cleaned every day?------yes it is为什莫填cleaned的过去式
问题描述：
is your classroom cleaned every day?------yes it is为什莫填cleaned的过去式
答
is your classroom cleaned every day?------yes it is
这边的cleaned不是过去式,而是过去分词,表示被动,用过去分词,表示教室是被打扫的
结构是【be+过去分词】