Làm hộ kèm gthich với ạ

6. Let's go to the school library this afternoon, A. aren't you B. shall we C. will we D. won't you 7. My mother has been busy. all afternoon. A. cooking B. cook C. to cook D. cooked 8. Is it possible to Sapa by motorbike? A. going B. to going C. to go D. go 9. We A. mustn't use public ...