作为非成员函数重载的运算符，所有操作数都必须以 ______ 的形式出现在参数表中。
参考答案：参数
——Alice looks sad. Did you tell her about the accident?
——Yes, but I ______ her just before her final examinations.
A．should have told
B．shouldn’t have told
C．needn’t have told
D．must have told
一产妇胎儿娩出后1h，胎盘未娩出， * * 未见出血，超声显示胎盘位于前壁，厚38mm，胎盘与子宫肌层间隙消失。此时诊断为（）
A.胎盘剥离
B.子宫卒中
C.胎盘粘连
D.低置胎盘
E.胎盘前置
