问题补充：
Her son cola, but now he milk.
A. used to drink; is used to drinking
B. used to drinking; drinks
C. is used to drinking; used to drink
D. is used to drink; is drinking
答案：
(答案→)A. used to drink; is used to drinking
B. used to drinking; drinks
C. is used to drinking; used to drink
D. is used to drink; is drinking
解析：be used to do sth,被用来做……，be used to doing sth 习惯于做……，used to do sth,过去常常做某事。句意：他的儿子过去常常喝可乐现在习惯于喝牛奶。故选A.
