— do you clean your room?
— Every day.
A. How long
B. How many
C. How often
D. How soon
网友回答
A. How long
B. How many
(答案→)C. How often
D. How soon
解析：词组辨析。How long 意为“多长”，是对时间或距离提问；how many 指多少，主要提问可数名词的数量；how often指每隔多久，主要提问频率；how soon指再过多久，主要提问表示将来的一段时间的量。根据答语every day可知是对频率提问，故C为正确答案。