a train of gears.

• 轮系

a train of gears.的用法和样例：

例句

1. There is a set of gear train models in the laboratory, which was bought from abroad at a high price.
   试验室里有一套轮系模型，是从国外高价买来的。
2. A description was carried out on the complicated epicyclic gear train by adopting the functional schematic diagram and the knowledge of graph theory.
   摘要采用功能示意图和图论知识对复杂周转轮系进行描述。