I/ Change into passive:

1. You can't wash this dress.

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2. You should open the wine about 3 hours before you use it.

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3. Members may keep books for 3 weeks.

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4. Passengers shouldn't throw away their tickets as inspectors (thanh tra) may check them during the journey.

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5. We  have to tow (kéo) the car to the garage.

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6. Visitors must leave umbrellas (dù, ô) and sticks (gậy) in the cloakroom (phòng treo áo khoác).

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7. You should take those books back to the library.

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8. We cannot exchange articles (món hàng) during the sale.

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9. You mustn't move this man; he's too ill.

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10.They ought to report the accident to the police. (ought to =should: nên)

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11. You must dry-clean it.

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12. You'll have to leave him here.

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