螺杆泵的从动螺杆只起（）液体从排空室漏回吸入室的作用。
A.促使
B.促进
C.阻止
D.加强
参考答案：C
The place _____ interested me most was the Children's Palace. [ ]
A. which
B. where
C. what
D. in which
暗管方式下穿放蝶形引入光缆的主要操作步骤有哪些？
