吹扫管线发生水击时，要迅速（）。
A．关小吹扫蒸汽
B．开大吹扫蒸汽
C．关闭吹扫后路阀
D．向上级报告
参考答案：A
—Can you go to the concert with us?
—Sorry, I can't. I have _____ homework.[ ]
A. too much
B. much too
C. too many
剖面每层样品采集（）左右。
A、0.5kg
B、1kg
C、1.5kg
D、2kg
