—How often does your sister surf the internet?
—About .
A. three time
B. three times
C. three time every day
D. three times a day
网友回答
A. three time
B. three times
C. three time every day
(答案→)D. three times a day
解析：How often 多久一次，句意：你的姐姐多久上一次网？ 大约一天三次。故选D。