skin ridges

例句：

1. 1. The old man's skin ridges are lined with wrinkles.
   老人的皮肤褶皱布满了皱纹。
2. 2. The baby's skin ridges are soft and smooth.
   婴儿的皮肤褶皱柔软光滑。
3. 3. The scientist studied the skin ridges of different species to understand their adaptations.
   科学家研究不同物种的皮肤褶皱以了解它们的适应机制。