以下哪种属于颌间固定（）
A.颌间结扎
B.小环结扎
C.连续多环结扎
D.带钩牙弓夹板
E.头帽固定
参考答案：A, B, C, D
Todd ________ a job in a bank, but to our surprise he didn’t take it.
A．offered
B．is offered
C．was offered
D．has offered
简析命令与令的关系。
