train-kilometer

例句：

1. 1. The train journey took us from the city to the countryside.
   火车旅程把我们从城市带到了乡村。
2. 2.He has a good knowledge of English and can speak it fluently in train-kilometers.
   他对英语有很好的了解，可以在火车里程中流利地说话。
3. 3.She planned to travel by train for the weekend.
   她计划周末乘坐火车旅行。