Đáp án đúng: Giải chi tiết:Had she not been seriously ill, she would/could/might have passed the exam. hoặc Had she not been seriously ill, she would not/wouldn’t/could not/couldn’t/ might not/mightn’t have failed (in) the exam. Trong câu điều kiện, If S + had not + V phân từ II = Had + S + not + Vphân từ II