valvelet

例句：

1. 1. The valves in the engine are responsible for controlling airflow.
   发动机中的阀门负责控制空气流动。
2. 2. The valves need to be adjusted regularly to ensure proper functioning.
   阀门需要定期调整以确保正常工作。
3. 3.The valves were designed to prevent leaks and improve efficiency.
   阀门被设计来防止泄漏并提高效率。