问题补充:
--Dad, why should I stopcomputer games?
--For your health, my boy, I’m afraid you.
A. to play; must
B. playing; have to
C. to play; can
D. playing; may
答案:
A. to play; must
(答案→)B. playing; have to
C. to play; can
D. playing; may
解析:have to 表示不得不,被逼的,而stop to do sth,表示停下去做某事,stop doing sth,表示停下手头正在进行的事,故选B