Musculi bulbi

例句：

1. 1. Musculi bulbi are a common sight in many animal species.
   肌肉球是许多动物物种中常见的特征。
2. 2. The muscle ball was used to help the child with his balance.
   肌肉球被用来帮助孩子保持平衡。
3. 3. In some species, muscle balls can be found on the underside of their tails.
   在一些物种中，可以在它们的尾巴下发现肌肉球。