Ex.3.Change these sentences into passive: 1. They are building that house now. 2. She bought a lot of flowers for her mother. 3. The children were eating all the vegetables and meat at 7p.m. 4. Lien didn’t finish her homework. 5. People use this cloth bag again and again. 6. You don’t prepare your lesson before you go to school. 7. He has written these books for the children for ten months. 8. Ha Long Bay attracts a lot of tourists. 9. Thu has seen that movie twice. 10. Vinh rented a car last week. 11. Mai does a test well 12. The teacher gives me mark 10 for my English test. 13. My mother cleans the floor everyday. 14. Mrs Lan usually feeds the dog. 15. Alexandar Graham Bell invented the telephone in 1876. 16. Nam repainted the school gate last week. 17. Christopher discovered America in 1949. 18. Minh has seen the accident on the road.