螺杆式空压机吸气滤清器的滤芯经过3次清理或使用多长时间，没有损坏也必须更换。（）
A、5个月
B、6个月
C、7个月
参考答案：B
But for these spelling mistakes, I ______a full mark in my last English examination.[ ]
A．got
B．had got
C．would get
D．would have got
溶剂再生塔C01001冲塔的原因是什么？
r these spelling mistakes, I ______a full mark in my last English examination.[ ]