—do you watch TV every day? — For about half an hour.A. How muchB. How oftenC. How longD.

问题补充：

—do you watch TV every day? — For about half an hour.

A. How much

B. How often

C. How long

D. How many

答案：

A. How much

B. How often

(答案→)C. How long

D. How many

解析：询问时间段时要用how long ，how many/much 是用来询问数量，how often询问频率