问题补充:
You need to brush your after .
A. tooth eat
B. teeth eating
C. tooth eating
D. teeth eat
答案:
A. tooth eat
(答案→)B. teeth eating
C. tooth eating
D. teeth eat
解析:句意:你需要在吃饭之后刷牙。brush teeth 刷牙,teeth 是tooth 的复数形式,根据句意可知,刷牙中的牙齿应该是复数的形式,故可排除A和C;after 在…之后,后面跟动词的ing形式。故选B。