EX4. Gach löi sai trong cac cau său Pol 1. My friend and I was at the hairdresser's yesterday. 2. My sister in law used to had long hair but now she has short hair. 3. Did your father worked in a tobacco factory before he retired? 4. Why you didn't come to the meeting last week? 5. My best friend and I use to hated each other when we first met. 6. Was Anna be successful with her project last week? 7. Yesterday morning I readed several chapters of the book "The little prince". 8. Last summer we involved in community service in our neighborhood, so we did go on holiday thành nôn hoàn chỉnh