镗削工件材料较硬时，镗刀的后角应取（）。
A.较小
B.小些
C.大些
D.较大
参考答案：B
When we were young, every evening my brother and I ______ stay at home waiting for our mother to come back from work.
A．would
B．might
C．should
D．could
链式栈与顺序栈相比，一个比较明显的优点是
A．插入操作更加方便
B．通常不会出现栈满的情况
C．通常不会出现栈空的情况
D．删除操作更加方便
