在常用的硬质合金刀具中，粗铣钢材时一般应优先选用（）牌号的硬质合金。
A.N
B.S
C.K
D.P
参考答案：D
You have no idea what I’ve had to ________ during the last few days.
A．come through
B．look through
C．cut through
D．go through
