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The best time to plant a tree was 20 years ago; the second-best time is now.

檢驗(yàn)假設(shè)有效性的唯一相關(guān)標(biāo)準(zhǔn)是其預(yù)測(cè)與經(jīng)驗(yàn)的比較。

"Hope is the only thing stronger than fear."

Great leaders are willing to sacrifice their own interests for the good of the team.