CNC铣床加工完毕后，为了让隔天下一个接班人操作更方便，可不必清洁床台。（）
参考答案：错
26．— Why are you still here? Everybody has gone to attend the lecture by the president.
— Oh, I__________about it!
A．wasn’t informed
B．hadn’t been informed
C．haven’t informed
D．didn’t inform
有块状结硬的水泥，只要不超过三个月可按常规用于砌筑砂浆内。 ( )
