So, think about the birches as a tool, another tool, but this time a tool for play, a tool for playing alone.

把桦树看成一种工具，另一种工具，但是这次是玩的工具，只是玩的工具。

耶鲁公开课 - 现代诗歌课程节选

You've got this policy tool of interest rates but once it hits zero you're out of business.

你拥有利率这一政策工具,但是一旦利率达到零点，你便失业了。

耶鲁公开课 - 金融市场课程节选

This is mainly a research tool now, but there's lots of reasons to believe that this is going to change the way that physicians practice medicine by allowing them to diagnose or predict what's going to happen to you in ways that they can't currently.

这项技术现在还只是一种研究工具,但我们有理由相信,它将改变,内科医生诊疗实践的方式,因为它能让医生,诊断或预测出病人将要得的病,这是他们现在做不到的

耶鲁公开课 - 生物医学工程探索课程节选