徒劳无功[ tú láo wú gōng ]

⒈ 徒劳的尝试或无用的姿态。例他们的种种失败，徒劳无功，简直像花儿和昆虫适合于共生一样惊人。英futility; make a futile effort; flog a dead horse; mount on a dead horse; shoe a goose; work to no avail;

⒉ 徒劳无成效的努力；常指空跑一趟而未遇见想要找的人。英water haul;