钻井转盘上平面到第一根套管接箍上平面之间的距离称为（）。
A、联顶节方入
B、完钻井深
C、油补距
D、人工井底
参考答案：A
Last week,only two people came to look at the house, __________wanted to buy it. [ ]
A. none of them
B. both of them
C. none of whom
D. neither of whom
什么是“有分别法”和“无分别法”？
