How do you study English ?I study English grammar.A. by learnB. by learningC. in learnD. i

问题补充：

How do you study English ?I study English grammar.

A. by learn

B. by learning

C. in learn

D. in learning

答案：

A. by learn

(答案→)B. by learning

C. in learn

D. in learning

解析：句意：你怎样学习英语？我通过学习语法来学英语。by 通过…方式后跟动词的-ing形式。故选B。