1. Someone stole her bag while she was walking home
2. They were having a picnic when it began to rain
3. I was cleaning my room when I found five pounds.
4. While the detective were looking in the car, they found an important clue или если как по образцу, то they found an important clue while
the detective were looking in the car, но первый вариант лучше звучит 5. John arrived while we were having dinner.