bell the cat系成语to hang the bell about the cat's neck的简略，愿意是“给猫的脖子上挂铃”。它来自《伊索寓言》(Aesop's Fables)中的《老鼠会议》(The Mice in Council)
这篇寓言讲的是：一群老鼠在鼠洞里举行会议，讨论如何对付凶狠的猫。白胡须老鼠提出：“我有个方法，在猫的脖子上挂一个铃。这样，猫一走动铃就响，我们就可以闻铃声而逃避了”，群鼠一致同意这个建议，欢呼：“That's a capital idea.We will bell the cat!No more fear of the cat!”但是，谁去给猫挂铃铛呢?没有一只老鼠敢去，一个个都溜掉了。老鼠会议豪无结果，它们不安全的境况当然也无法改善。
寓言所寄托的意思很明白：遇到困难的问题时候，既需要有出谋献策的人，更需要有挺身而出的实干家。
bell the cat常用来比喻to do sth dangerous in order to save others;to step forwar bravely to face the danger;to take a risk for the good of others.
eg:Everybody made suggestion,but no one actually offered to bell the cat.
We didn't know who would put him this delicate question when my friend offered to bell the cat.