pony rod

例句：

1. 1. The pony was so excited that it jumped straight into the arena.
   那匹马太兴奋了，直接跳进了赛马场。
2. 2. The pony rod is a crucial part of a horse's equipment.
   马鞍杆是马装备中至关重要的一部分。
3. 3. The pony rod helps to distribute weight evenly across the horse's back.
   马鞍杆有助于均匀地将重量分布在马背上。