To engage in a futile or pointless endeavor; to waste one's efforts on something impossible or impractical.
没有合适的工具和专业知识，想在短时间内完成这个复杂的项目，简直是抟沙作饭，白费力气
Without the right tools and professional knowledge, trying to complete this complex project in a short time is simply molding sand into a meal, a complete waste of effort.
Era:
Early Modern
Frequency:
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