to milk the bull
01
白费力气, 做无用功
to engage in a fruitless or pointless activity
![to [milk] (the|a) (bull|ram) definition and meaning](https://cdn.langeek.co/photo/41244/original/?type=jpeg "to [milk] (the|a) (bull|ram) definition and meaning")
disapproving
idiom
informal
old use
例子
The politician's attempts to win over the opposing party were like trying to milk a bull - they were never going to work.
我们花了几个星期修一个早就没人用的系统，完全是白费力气。
