上皮

例句：

1. 1. The epidermis of the skin is the outermost layer that protects us from the environment.
   皮肤的表皮是我们身体最外层的一层，它保护我们免受外界环境的伤害。
2. 2. The epidermis of the eye is thin and transparent, allowing light to pass through.
   眼睛的表皮很薄且透明，允许光线通过。
3. 3. The epidermis of the skin is constantly renewed by cells called keratinocytes.
   皮肤的表皮由称为角质细胞的细胞不断更新。