电子对抗的主要内容？
参考答案：
无线电通信对抗、雷达对抗、光电（红外、激光）对抗、水声对抗等。
— What ______ you ______ for this winter holiday?
— I'm not sure, Maybe I'll just stay at home. I'll have a big test after the holiday. [ ]
A. did, do
B. are, doing
C. do, do
D. were, do
加长电缆插头与连接到的覆盖电缆插头，要做到（）一一对应。
A、针针号
B、孔孔号
C、针孔号
D、插头号
