问题补充：
---- does take to play tennis? ----Let me see. About two hours.
A. How; it
B. How long; it
C. How; he
D. How long; he
答案：
A. How; it
(答案→)B. How long; it
C. How; he
D. How long; he
解析：回答语表示的含义是时间长度两个小时，对此提问的用how long，问句的含义是打网球需要花费你多长时间，主语用形式主语it来代替真正主语to play tennis，故本题选B。
