为了防止受电弓活动关节轴承的产生电腐蚀，因此要用编织铜带将其活动关节短接。
参考答案：对
________full preparations, we decided to put off the meeting till the next week. [ ]
A. We did not make
B. We had not made
C. Not having made
D. Having not made
关于地球形状的说法，正确的是（ ）
A．地球是一个圆
B．地球是一个规则的正球体
C．像橄粒一样的椭球体
D．两极稍扁赤道略鼓的椭球体
