—How do you learn English？ —I learn English by .A. listen to cassettes　　　　　　　　　　B. speak i

问题补充：

—How do you learn English？ —I learn English by .

A. listen to cassettes

B. speak it

C. listening to cassettes

D. ask the teacher

答案：

A. listen to cassettes

B. speak it

(答案→)C. listening to cassettes

D. ask the teacher

解析：句意：--你怎样学英语的?---我通过听磁带学的。by“通过”是介词，后面应该跟名词或动名词，在选项中只有C是动名词形式。所以本题选C。