There are many ways in which you can improve your study. But you should work hard.A. af

问题补充：

There are many ways in which you can improve your study. But , you should work hard.

A. after all

B. above all

C. for all

D. in all

答案：

A. after all

(答案→)B. above all

C. for all

D. in all

解析：

词组辨析:after all毕竟above all最重要的是 for all尽管，虽然in all总共，根据句意：有很多方式可以提高英语，但最重要的是,你应该努力学习。