问题
选择题
--Dad, why should I stop computer 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
答案：B
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