SELV

例句：

1. 1. The ecosystem is in a state of equilibrium.
   生态系统处于平衡状态。
2. 2.Ecological studies are essential for understanding the environment.
   生态学研究对于理解环境至关重要。
3. 3.The conservation of biodiversity is crucial for maintaining ecological balance.
   保护生物多样性对于维护生态平衡至关重要。