rotten seedling of kelp

例句：

1. 1.The rotten wood in the trunk is dangerous to climb.
   树干里的腐烂木头很危险，不能爬。
2. 2. The old book was rotten with dust.
   那本旧书满是灰尘。
3. 3. The food was rotten and had to be thrown away.
   食物腐烂了，不得不扔掉。