—How do you study English well?— working hard.A. ByB. AtC. FromD. With

问题补充：

—How do you study English well?

— working hard.

A. By

B. At

C. From

D. With

答案：

(答案→)A. By

B. At

C. From

D. With

解析：考查点：介词辨析。解题思路：by 表示方式，手段。