车削时使用的车刀结构主要有什么？
参考答案：整体式、焊接式和机械夹固不重磨的可转位硬质合金车刀等。
You should be yourself and celebrate because _____. [ ]
A. no one is quite like you
B. you're very clever
C. you are a good student
D. you have many talents
上门收款服务证由（）保管
A、上门收款人员
B、管库员
C、网点业务主管
D、保卫部门
