离心泵不上量的原因一般有那些？
参考答案：
泵内有气体未排尽，管道堵塞，进口阀开度过小而出口阀开度过大，泵内叶轮损坏或与传动轴连接松脱。
—Would you like _____ football with us?
—Sure. I like _____ football very much.[ ]
A. to play; playing
B. playing; play
C. to play; to play
D. playing; to play
胶带输送机胶带纵向裂口不超过200mm视为完好。
