Odpowiedź:
1. I WAS HAVING a break, when mum CAME in.
2. The two boys WERE BULLYING some younger students when the deputy head CAUGHT them.
3. Jane's parents GOT her exam results while she WAS TRAVELLING around Europe.
We use the past continuous tense here to describe the situation that existed at that time and to show that a longer action in the past was interrupted. The interruption is usually shown in the past simple tense