Từ 13->21 ạ....................

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13. The cats had been fed by Ann before she went to the cinema.
14. The pollution problems have been discussed by the students since last week.
15. Has the most valuable painting in the national museum been stolen by the thieves?
16. The new president will be interviewed on TV.
17. How many languages are spoken in Canada?
18. Are those shoes going to be repaired?
19. His nose has been broken in a football match.
20. Have the above sentences been finished?
21. Rice is eaten by him everyday.
22. This cake was made yesterday.