variable capacity pump

例句：

1. 1.The variable capacity pump is used to control the flow rate of the water.
   可变容量泵用于控制水的流速。
2. 2. The variable capacity pump can be adjusted to meet the changing needs of the water system.
   可变容量泵可以调整以满足水系统不断变化的需求。
3. 3.The variable capacity pump is an essential tool for maintaining the efficiency of the water system.
   可变容量泵是维护水系统效率的必备工具。