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1. Yesterday when he carried a suitcase he was dropping it on his foot.
2. He was breaking his leg when he skied last month.
3. He was sitting down on chair when I painted it.
4. Lan was sitting in the garden when a wasp stung her on the nose.
5. As we were driving down the hill, a strange object appeared in the sky.
6. Tam was playing football when we saw him yesterday.
7. While my mother was cooking, my father was playing chess with my brother.
8. I didn't see you at the party yesterday. Where were you?
9. Tony had an accident yesterday because he drove carelessly.
