telegraph

在紧急情况下，他们通常用电报发送重要信息。

In emergencies, they usually ___telegraph important messages.

战争期间，他们通过电报传递紧急军情。

During the war, they communicated urgent military information by ___telegraph.

在19世纪，电报是跨大陆通信的主要方式。

In the 19th century, the ___telegraph was the main method for cross-continental communication.