gǔ / rén / céng / jīng / xùn / liàn / chuán / shū / gē / bǎ / xìn / jiàn / sòng / dào / yuǎn / fāng

古人曾经训练传书鸽，把信件送到远方。

In ancient times, people trained carrier pigeons to deliver messages to distant places.