Use past simple or past progressive to complete the sentences. 1. When we (arrive) at the hotel, there (be) no rooms available. The conference of ecologists (open) that day. 2. When I (enter) the dining room, Kitty (sit) at table. Not being hungry she (pick) at her food. 3. We (walk) along the street when suddenly we (see) Graham. He (drive) a brand-new Mitsubishi. 4. Jane (sit) in the armchair for a quarter of an hour and then (fall) asleep. 5. John was an obedient child as a rule but that day he (be) extremely naughty. 6. The boys (play) football all day long. 7. We all (stay) in the sitting room during the ceremony. 8. The whole day all members of the family (prepare) their cottage for the occasion. 9. The old gentleman (stroll) along the path for a while, then abruptly (turn) back and (start) for the house. 10. Jack (tell) me that his elderly aunt (feel) much better at the moment. 11. I (phone) you several times in the morning but nobody (answer). 12. I wonder what he (do) at nine o'clock in the evening. 13. While Jenny (clean) the floors, her little sister (play) computer games. 14. It (be) early autumn. The sun (shine) in the blue sky but the trees (get) yellow and the birds (fly) to warm countries. 15. Mrs Evans (stand) on the edge of a cliff admiring the view.

Sure! Here are the sentences with the correct forms of the verbs in either past simple or past progressive:

1. When we arrived at the hotel, there were no rooms available. The conference of ecologists opened that day.
2. When I entered the dining room, Kitty was sitting at the table. Not being hungry, she was picking at her food.
3. We were walking along the street when suddenly we saw Graham. He was driving a brand-new Mitsubishi.
4. Jane sat in the armchair for a quarter of an hour and then fell asleep.
5. John was an obedient child as a rule, but that day he was extremely naughty.
6. The boys were playing football all day long.
7. We all stayed in the sitting room during the ceremony.
8. The whole day all members of the family were preparing their cottage for the occasion.
9. The old gentleman strolled along the path for a while, then abruptly turned back and started for the house.
10. Jack told me that his elderly aunt was feeling much better at the moment.
11. I phoned you several times in the morning, but nobody answered.
12. I wonder what he was doing at nine o'clock in the evening.
13. While Jenny was cleaning the floors, her little sister was playing computer games.
14. It was early autumn. The sun was shining in the blue sky, but the trees were getting yellow, and the birds were flying to warm countries.
15. Mrs. Evans was standing on the edge of a cliff admiring the view.