胁痛的病因病机有（）
A.肝气郁结
B.瘀血阻络
C.湿热蕴结
D.肝阴不足
E.脾肾阳虚
参考答案：A, B, C, D
It’s said that there are plenty of hotels in that town. There _____ be any difficulty for you to find
one to stay in. [ ]
A. mustn’t
B. oughtn’t
C. shouldn’t
D. needn’t
离心式压缩机的轴向力的70%采用（）来平衡。
A、平衡盘
B、平衡孔
C、平衡管
D、叶轮对称布置
