导压管的材质与工艺管道要求相同，按介质的( )等因素选择。
A．流量
B．温度
C．压力
D．腐蚀性
参考答案：B,C,D
管形皮瓣有哪些优点?
You'd better give up smoking, Tom, for many diseases are ________ to smoking, you know.[ ]
A. linked
B. led
C. exposed
D. blamed
