1. He (read) an interesting book last month. 2. Sam (read) an interesting book in the morning. 3. We (discuss) this film when you arrived. 4. She (knock) and (come in). 5. They (watch) TV and went for a walk. 6. The boy (watch) TV at six o'clock. 7. My friend (introduce) me to his mother.

Past Simple / Past Continuous:

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.