ring runner

例句：

1. 1. The racers completedthe course in a ring runner.
   赛跑者在环形跑道上完成了比赛。
2. 2. Theengineer designed a circular run for the constructionsite.
   工程师为工地设计了一个环形轨道。
3. 3. Theworkers used a circular conveyor belt totransport materials efficiently.
   工人们使用环形传送带高效地运输材料。