these days students in some schools are asked not to use mobile phones

问题描述:

these days students in some schools are asked not to use mobile phones
这个的主语是什么?难道不是学生吗?为什么这句话是被动语态.(我还没学).我看到被动语态句子的结构 一般动词在人称的前面 还有个by.这句话 就不是啊.求教

(1) 是被动语态: students in some schools are asked ( by their headmasters=省略了) not to use mobile phones
(2) 如不是被动语态: students in some schools are [asking] their headmasters for permission to use mobile phones.被动语态主语不是应该跑到后面去了。。。。主语是啥 是学生吗。。(3) 主语(subject) 应是"these days students in some schools" 我不是很了解句子分析