怀疑流脑时首先应做( )
A．头颅CTB．使用抗菌药物C．腰穿送脑脊液检查D．头颅x光片E．血常规检查
参考答案：C
Our teachers promised to attend our class meeting, but they haven’t ____ yet.
A．turned up
B．turned out
C．reached
D．turned over
（）与数控系统的插补功能及某些参数有关。
A．刀具误差
B．逼近误差
C．插补误差
D．机床误差
