1. They have just told us about that.
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2.Someone has stolen the book on the shelf.
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3.Nobody has cleaned the floor since 7:30P.M.
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4. The teacher returned our written work to us.
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5. The doctor ordered him to take a long rest.
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6. They didn’t allow Tom to take these books home.
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7. Nobody swept this street last week
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8. The boys broke the window and took away some pictures
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9. Tom was writing two poems
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10. The chief engineer was instructing all the workers of the plan
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11. Alex was preparing that report when I came to see him.
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12. Mary was helping her mother in the kitchen at the time.
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13. She was watching an interesting show on the TV at 8 o’clock last night.
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14. The teacher won’t correct exercises tomorrow
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15. They will hold the meeting before the May Day
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16. They have to repair the engine of the car
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17. They may use this room for the classroom
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18. The teacher is going to tell a story
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19. She used to pull my hat over my eyes
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20. You mustn’t use the machine after 5.30 p.m
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21. You must clean the wall before you paint it
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