轨道绝缘及第一绝缘点的设置要求有哪些？
参考答案：不回电的轨道与架线电机车回电轨道之间，必须加以绝缘。第一绝缘点设在2种轨道的连接处。
________ abroad for a tour can be a great honor for an ordinary person like me.
A．Taking
B．Taken
C．Being taken
D．Having been taken
