外螺纹钻杆
参考答案：
两端具有外螺纹的钻杆。被代替的同义词：“外丝钻杆”。
Mr Black has ______ friends in that city because he never lives or studies there. [ ]
A. many
B. a few
C. a lot of
D. few
上例的货物进口的转关方式是( )。
A．提前报关转关
B．直转转关
C．自转方式的转关
D．中转方式的转关
