清管球清扫管道时,推球压力可以为()。
A、0.2MPa
B、0.3MPa
C、0.5MPa
D、0.6MPa
E、0.7MPa
参考答案:A, B, C, D
—This is _____ film I've told you about several times.
—That's great. I've never seen _____ more moving one.[ ]
A. a ; a
B. the ; the
C. the; a
D. a ; the