Chuyển các câu sau sang thể bị động

Chuyễn các câu sau sang thể bị động
1) The boy hears them singing a song.
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2) He watches her clean the floor
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3) She watched him repair the car.
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4) I saw th boys playing games.
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5) I noticed the students write in English .
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6) They saw her washing clothes
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7) Mai notices me do the exercisee.
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8) Lan watches her friends plant the trees.
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