無む駄だ足あしを踏ふむ

expression, godan verb (-mu)

go on a fool's errand; go in vain

Used when a trip or visit turns out to be pointless, often because the purpose was already lost or the person was absent.

• わざわざ行いったのに、店みせが閉しまっていて無む駄だ足あしを踏ふんだ。

  I went all the way there, but the shop was closed and it was a wasted trip.

• 事じ前ぜんに電でん話わで確かく認にんしないと、無む駄だ足あしを踏ふむことになるよ。

  If you don't call ahead to check, you'll end up going for nothing.