在硬材料上钻孔时，应（）。
A.转速快些，进给量大些
B.转速慢些，进给量小些
C.转速快些，进给量小些
D.转速慢些，进给量大些
参考答案：B
磁州窑的鼎盛期在（）。
A.唐宋
B.宋辽
C.宋金
D.元明
If you are an energetic person with p views as to the right way of doing things, you find yourself________ under pressures.
A．variably
B．invariably
C．invaluably
D．invalidly
