guò / qù / diàn / bào / yuán / xū / yào / shú / liàn / zhǎng / wò / diàn / mǎ / cái / néng / zhǔn / què / fā / sòng / xìn / xī

过去电报员需要熟练掌握电码，才能准确发送信息。

In the past, telegraph operators had to master telegraph code to send messages accurately.