1. That is my grandfather. (改为一般疑问句) ______ that _____ grandfather? 2. This is an orange. (改为复数句) ______ ______ oranges. 3. His backpack is on the desk. (对划线部分提问) ______ ______ his backpack? 4. John has three baseballs. (改为否定句) John ______ ______ three baseballs. 5. Does Linda play ping-pong every morning? (作否定回答) ______, she ______.