Open the brackets and use the Past Continuous Tense or the

Open the brackets and use the Past Continuous Tense or the Past Simple Tense:
1. She ( dance) when I ( come)
2. They ( play chess) when the telephone ( ring)
3. He ( read) the book when the storm ( begin)
4. We ( swim) all the morning
5. Yesterday he ( cook) before his mother ( arrive)