#1
1) He read an interesting book last month.
2) Sam was reading an interesting book in the morning.
3) We were discussing this film when you arrived.
4) She knocked and came in.
5) They watched TV and went for a walk
6) The boy was watching TV at six o'clock.
7) My friend introduced me to his mother.
#2
1)We have just begun our lesson.
2) He has already introduced us.
3)I left my copybook at home yesterday.
4)She got a bad mark last week.
5) Mike has read this exercise before the lesson.
6) Sam and I met a week ago.