切边剪剪切钢带，最大剪切厚度（）㎜；
A.3
B.4
C.5
D.6
参考答案：C
---Alice, why didn’t you come yesterday?
--- I______, but I had an unexpected visitor.
A．had
B．would
C．was going to
D．did
在脓疱疮的早期，首选的物理治疗是
A．超短波
B．激光
C．紫外线
D．热敷
E．红外线
