1. when
2. while
3. while
4. while
5. while
6. when
7. while
8. when
2)
1. I was having a great time.
2. She was phoning her grandparents.
3. John was learning the past continuous.
4. Our grandparents were visiting us.
5. I was trying to understand tis exercise.
6. Our teacher was explaining a difference between an adjective and an adverb.