1) My father had done the shopping by five o'clock.
2) When I came home, my mother had already cooked dinner.
3) I hadn't seen Sue for many years before I suddenly met her in the street.
4) Kate gave me the book which she had bought the day before.
5) Had you worked before you entered the institute?
6) When I came home, my sister had already got a letter from our granny.
