钻削的切削转速是指钻头（）的旋转周数。
A、每秒钟
B、每分钟
C、每小时
D、两小时
参考答案：B
---Could I make it 14th July?
--- __________.
A．You can manage it.
B．That’s fine with me.
C．Not a bit of it.
D．Go ahead with it.
河漫滩形成于河流的（）
A、凸岸
B、凹岸
C、凸岸和凹岸均可
D、都不对
