Aj型安全接头下井前一定要做好检查，要看（）（）锯齿镙纹及密封圈是否完好
参考答案：公、母
The idea they have come up with sounds great, but it remains whether it works well in practice．
A．to see
B．to be seen
C．seeing
D．seen
汽车诊断参数包括（）参数、（）参数和（）参数。
