up a blind alley
走进了一条死胡同，没有出路，没有希望
书面/口语·形容徒劳的努力
英文释义
to be in a situation that leads nowhere; to be faced with a dead end; to be pursuing a fruitless or pointless endeavor
例句
His research went up a blind alley after months of work with no results.
典故来源
源自城市布局：盲巷指没有出口的死胡同，比喻努力方向错误或毫无进展。