1. I HAVE already WRITTEN a letter to my friend.
2. You HAVE already OPENED the window.
3. He DIDN'T CALL his friend the day before yesterday .
4. They BOUGHT a new computer yesterday.
5. Yesterday at six o’clock we WERE PLAYING football.
6. He HAD PHONED his friend before he went to the theatre.
7. When she received a telegram her brother HAD already LEFT.