He writes to his e-friend once a month.对once a month提问
问题描述:
He writes to his e-friend once a month.对once a month提问
答
How often does he write to his e-friend ?
答
how ofen
答
How often does he write to his e-friends?
答
How often does he write to his e-friend?
答
对频率提问用how often.
所以How often does he writes to his e-friend