reverse gear train

例句：

1. 1. Theengineer designed a reverse gear train to improve the efficiency of the machine.
   工程师设计了一个倒档齿轮组来提高机器的效率。
2. 2.The car's engine has a reverse gear train that allows for easy reversing.
   这辆车的引擎有一个倒档齿轮组，可以轻松地倒车。
3. 3.The train's engineer installed a reverse gear train to make it easier to maneuver in tight spaces.
   火车的工程师安装了倒档齿轮组，使在狭窄空间中操作更容易。