Computers are so popular in our country that every pupil knows e-mails.A. how can he send

问题补充：

Computers are so popular in our country that every pupil knows e-mails.

A. how can he send

B. how does he send

C. how to send

D. how sending

答案：

A. how can he send

B. how does he send

(答案→)C. how to send

D. how sending

解析：本题know后跟的是从句，应该用正常顺序，故不选AB，在英文中，可用疑问词+动词不定式to do代替从句，故本题选C。