fluid flywheel

例句：

1. 1. The engine is running smoothly with the correct amount of oil.
   发动机以正确的油量运行顺畅。
2. 2. The liquid in the bottle has turned to a gel.
   瓶子里的液体已经变成了凝胶。
3. 3. The liquid level in the tank needs to be checked regularly.
   油箱中的液体水平需要定期检查。