While my mother watched TV, I was cooking dinner.
When I came home, my mother was having breakfast.
She was doing her homework at 4 o'clock yesterday while I was at school.
My aunt was writing a letter to me at 5 o'clock yesterday while I was on my way to my grandmother.
My uncle called me a few times while I was decorating a Christmas tree.
My brother and sister were playing basketball, while I was at canteen.