He did not work hard. He failed the exam.
Unless he had worked hard, he would have failed the exam.Even though he failed the exam, he didn’t work hard.If he had worked hard, he would have passed the exam.However hard he worked, he failed the exam.Hướng dẫn giải:Dịch nghĩa: Nếu cậu ấy học chăm, cậu ấy đã qua kỳ thi rồi.
