Chuyển những câu bị động dưới đây thành câu chủ động: 1 A gift was sent to me by my old students .2. You are not allow by the teacher to cheat in the exam, 3. My table is being fixed by my father .4. How long has this fax machine been used by Mr. Green? 5. The singer was not recognized by his fan when he was at the restaurant 6. He will be disqualified from the competition by the judges if he uses 7. All the unnecessary lights will be turned off to save energy 8. Jane was prevented from staying up too late by her mother 9. Was this document typed by Mr. Brown? 10. Many dead people were found by the rescuers after the earthquake