两顶尖装夹的优点是安装时不用找正，（）精度较高。
A、定位
B、加工
C、位移
D、回转
参考答案：A
网络优化主要从()等方面来进行分析。
A.掉话率
B.无线接通率
C.切换
D.干扰
E.上下行速率
Three days after Mrs White’s _______ necklace was found, she was _____ it.
A．lost; robbed
B．Missed; robbed of
C．lost; robbed of
D．missing; robbed
