working steam

例句：

1. 1.The machine needs to be worked with a new oil to maintain its efficiency.
   这台机器需要用新的油来保持其效率。
2. 2.The working steam is responsible for driving the pistons.
   工作蒸汽负责推动活塞。
3. 3. The engineer used working steam to cool down the metal before it was cut.
   工程师使用工作蒸汽来冷却金属，然后再进行切割。