按照薄钢板防腐油漆喷涂要求，在含有粉尘或粉屑空气的风管，外表面涂面漆（）遍。
A、1
B、2
C、3
D、4
参考答案：B
53. I’m afraid I can’t keep _______ my classmates as I’ve missed so many lessons. I have to ask my teacher for help.
A．up
B．with
C．up with
D．on with
真丝服装怎样洗涤？
