extra train

例句：

1. 1.We need to reserve a seat on the extra train for our family.
   我们需要为我们的家庭成员预订额外列车的座位。
2. 2. The extra train will arrive at the station an hour later.
   额外列车将在一小时后到达车站。
3. 3.The extra train service is very convenient for travelers who need to travel long distances.
   额外列车服务对于需要长途旅行的旅客来说非常方便。