Đáp án đúng: Giải chi tiết:Peter apologised/apologized (to the/his teacher) for not doing the/his homework. hoặc Peter apologised/apologized (to the/his teacher) for not having done the/his homework. Cấu trúc “apologize to sb for doing st (not doing st)”: xin lỗi ai vì đã làm gì (không làm gì)