two-stage pump

例句：

1. 1. The two-stage pump is designed to improve efficiency by reducing the number of stages in the process.
   两级泵通过减少过程中的级数来提高效率。
2. 2. In this application, a two-stage pump is used to separate oil from water.
   在这个应用中，使用两级泵将油从水中分离出来。
3. 3. The two-stage pump has been proven to be more energy efficient than traditional single-stage pumps.
   两级泵已被证明比传统的单级泵更节能。