V. Nổi các câu sau sử dụng mệnh đề quan hệ. (Lưu ý cách dùng dấu phẩy) Mrs. Quyen does volunteer work at the hospital. She is retired teacher. 1. The man called the police. His wallet was stolen. 3. Last summer I spent my vacation in Sa Pa. My friend is working in it. The museum has just been built recently. We visited it last month. The professor is strict. We know his wife. 2. 4. 5. in bad light he will ruin his eyes.
