To make futile efforts, acting in a counterproductive way that makes one's objective impossible to achieve.
他一边想提高工作效率，一边又整天沉迷于玩乐，这简直是戴盆望天，怎么可能成功呢？
He wants to improve his work efficiency, yet he spends all day indulging in leisure. This is like trying to see the sky with a basin on his head – how can he possibly succeed?
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