褐斑

例句：

1. 1. The old painting has several brown spots on it.
   这幅旧画上有好几个棕色的斑点。
2. 2. The sun's rays have left a few spots on the grass.
   太阳的光线在草地上留下了几个斑点。
3. 3. The book has several yellow spots that need to be cleaned up.
   这本书有几处黄色的污点需要清理。