We/ ought/ study/ hard/ please/ our parents.3/15 We/ ought/ study/ hard/ please/ our parents.We ought to study hard to please our parents.We ought studying hard to please our parents.We ought to study hard to pleasing our parents.We ought to studying hard to please our parents.Giải thíchĐáp án A Dịch: Chúng ta phải học hành chăm chỉ để không phụ lòng cha mẹ.