As middle school students, we the police to keep order.
A. are used to help
B. used to helping
C. used to help
D. used to be helped
网友回答
A. are used to help
B. used to helping
(答案→)C. used to help
D. used to be helped
解析： used to do sth. 过去常常做…；be used to doing sth.习惯语做…。