Ex. 10.
1. I met a friend while a was doing the shopping.
2. I was paying for my things when I heard someone call my name.
3. I was turning round and saw Jo.
4. She wore a bright red coat.
5. We decided to have a cup of coffee.
6. While we were having a drink, a waiter dropped a pile of plates.
7. We all got a terrible shock.
8. While the waiter was picking up the broken plates, he cut his finger.