When the teacher came in,we were talking.哪个是主句,哪个是从句?

When the teacher came in,we were talking.哪个是主句,哪个是从句? 小题1:We were talking loudly when the teacher came in . (对划线部分 While we were talking,the teacher came in.此句 可不可以用when代替whil they were talking loudly when the teacher came in They were talking _______ when the teacher came in While we were talking,the teacher came in We were talking about English （before the teacher came in）,变 the students stopped talking when the teacher came in The students stopped talking () when the teacher came in. The students------(stop)talking when the teacher came in when the teacher came in ,we stop ( ) when the teacher came in,we were reading.(用while改写句子）