treadmill

n.踏车；繁重的工作；跑步机

A dog formerly used in a treadmill to turn a roasting spit. 以前用在踏车上转动烤肉叉的狗

I can't get off the office treadmill. 我无法摆脱单调的坐班工作。

Theoretically there is no limit to the size of treadmill. 理论上跑步机的大小是没有限制的。