circulatory pool

例句：

1. 1. The hospital has a circulatory pool that is used for patient care.
   医院有一个循环池，用于病人护理。
2. 2. The circulatory pool helps to maintain the water quality in the lake.
   循环池有助于维护湖泊的水质。
3. 3. In the circulatory pool, fish swim up and down, feeding on plankton.
   在循环池中，鱼上下游动，吃着浮游生物。