---How often does he go to the Swimming Club?-.A. Two hoursB. TwiceC. Two a dayD. Twice

问题补充：

---How often does he go to the Swimming Club?

---.

A. Two hours

B. Twice

C. Two a day

D. Twice a week

答案：

A. Two hours

B. Twice

C. Two a day

(答案→)D. Twice a week

解析：how often是对频率进行提问，只有D表示频率，A表示时间长度，B表示次数，

C结构不正确，故只能选D。