They have destroyed these buildings since 1990

11. They have destroyed these buildings since 1990.
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12. We haven't finished our work yet.
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13. We can't make tea with cold water.
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14. The thief has stolen the most valuable picture.
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15. My sister can solve the problems very quickly.
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16. He has broken his nose in a football match.
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17. Have you finished the above sentences?
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18. Nobody can make that cake.
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19. Have you sent this postcard to your best friend?
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20. We shouldn’t eat too much junk food.
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