agnathan

例句：

1. 1. The agnathan is the only creature that can breathe underwater.
   这种生物是唯一一个能在水下呼吸的生物。
2. 2. The agnathan has a unique ability to sense vibrations in the water.
   这种生物有一种独特的能力，可以在水里感知到振动。
3. 3. The discovery of this agnathan species has sparked debate about its role in the ecosystem.
   这种生物的发现引发了对它在生态系统中作用的辩论。