签字厅的布置要求( )。
A.隆重、热烈
B.使用正规的签字桌
C.签字桌置于门
D.签字桌后不必摆放座椅
参考答案:B
--- May I go now?
--- No. You ______________ let the teacher know first.”
A.need
B.must
C.can
D.may
胎盘剥离面超过胎盘的1/3为重度胎盘早剥