涡轮钻具
参考答案：
把钻井液的水力能经过叶轮转换成机械能的动力钻具。
可作为氯霉素滴眼剂PH调节剂的是
A．10%HCL
B．硼砂
C．尼泊金甲酯
D．硼酸
E．硫柳汞
It is universally agreed that parents should keep _____ in educating their children.[ ]
A. constructive
B. cautious
C. consistent
D. convenient
