buck rack

例句：

1. 1. The horse was so tired that it couldn't even stand upright.
   那匹马太累了，站都站不起来。
2. 2.She rode her horse to the stables every day.
   她每天骑马去马厩。
3. 3. The rider had to shift his weight back and forth to keep the buck rack from slipping off.
   骑手不得不来回调整身体重量，以免鞍子滑落。