Rewrite these sentences

1) Rewrite these sentences.
11. They  are selling cookies  for christmas right now.
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12. Tom will give Anna a ride to school tomorrow.
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13. Their grandmother told them this story when they visited her last week.
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14. Tim has to order this train ticket for his mother.
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15. Have our teachers explained the English grammar ?
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16. Some drunk drivers caused the accident in this city.
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17. Her mother is preparing the dinner in the kitchen.
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18. The boys had not finished the homework before going to school.
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