直肠上、下静脉丛在何处互相交通：
A．齿线
B．栉膜带
C．肛门白线
D．肛管直肠环
E．以上均不对
参考答案：C
Stop_________! I have_______ to tell you.
A．talking, something important
B．talking, important something
C．to talk, anything important
D．to talk, important anything
生产中发生仪表风中断，凝聚工序应首先（）。
A.停喷胶
B.停加热蒸汽
C.将各调节控制点改为副线操作
D.通知干燥停车
