forward shaft

例句：

1. 1. The machine's forward shaft is the only thing thatmoves.
   这台机器的推进轴是唯一一个移动的部分。
2. 2. The engineer had to replacethe forward shaft of the engine.
   工程师不得不更换发动机的推进轴。
3. 3. Thenew design uses a forwardshaft to reduce friction and improveefficiency.
   新设计使用一个推进轴来减少摩擦并提高效率。