gym-horse

例句：

1. 1. The gym-horse is a popular breed of horses used in equestrian sports.
   马术运动中的马是一种受欢迎的马种，用于马术运动。
2. 2. The gym-horse was trained to perform at the Olympics.
   这匹马被训练参加奥运会表演。
3. 3. The gym-horse is a symbol of strength and endurance.
   马术运动中的马象征着力量和耐力。