使用对讲机进行通话时，先按住“（）”，距离“麦克风”（）至（）说话，说话完毕时松开“（）”，即可收听对方语音信息。
参考答案：通话键；2.5；5厘米；通话键
A．(A) He is sometimes not on good terms with his parents.
B．(B) He wants to have control over his parents.
C．(C) He and his parents are not fond of each other.
D．(D) He and his parents have different views about family life.
哪种导航显示允许飞行计划的检查（）。
A.地图方式
B.VOR方式
C.导航方式
D.计划方式
