Crinozoa

例句：

1. 1. The protozoa in the water are constantly moving around.
   水中的原生动物一直在不停地移动。
2. 2. Many scientists believe that protozoa play an important role in the ecosystem.
   许多科学家认为原生动物在生态系统中起着重要的作用。
3. 3. The protozoa were found to have a unique ability to resist disease.
   研究发现，这些原生动物具有抵抗疾病的独特能力。