桡骨下端的掌倾角正常应为：
A．5°～10°
B．10°～15°
C．15°～20°
D．25°～30°
E．30°～35°
参考答案：B
There’re ______ fish in the pond( 池塘). They’re very lovely.
A． a little
B．little
C．few of
D．a lot
用立轴给进油缸下降钻具时，卷扬机钢丝绳要处于张紧状态
