To overestimate one's own power or influence and attempt something far beyond one's capabilities, an utterly futile endeavor, like an ant trying to shake a huge tree.
那个刚成立的小公司，妄图与行业巨头竞争，简直是蚍蜉撼大木，最终只会徒劳无功。
That newly established small company, attempting to compete with industry giants, is simply an ant trying to shake a huge tree, and will ultimately achieve nothing but futility.
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