my brother was singing while my mother was cooking= my brother was singing when my mother was cooking= while my mother was cooking,my brother was singing = when my mother was cooking,my brother was singing 语法都对吧

问题描述:

my brother was singing while my mother was cooking= my brother was singing when my mother was cooking= while my mother was cooking,my brother was singing = when my mother was cooking,my brother was singing
语法都对吧

是一样的.
语法都对