engine telegraph repeater

例句：

1. 1. The engineer installed the telegraph relay in the factory to improve communication efficiency.
   工程师在工厂安装了电报中继器，以提高通信效率。
2. 2. The telegraph repeater was crucial for maintaining communication during the war.
   在战争中，电报中继器对于保持通信至关重要。
3. 3. The engineer replaced the old telegraph repeater with a more modern model.
   工程师用更现代的型号替换了旧的电报中继器。