作堅持不懈的努力 make unremitting efforts
只要妳堅持不懈，妳自會成功。 Persevere and you'll succeed.
廣大勞動人民堅持不懈地進行鬥爭，終於迫使清政府不敢公然和帝國主義續訂新約。 The broad working masses were undaunted, and persisted in their struggle with the result that the Qing government did not dare to conclude a new treaty with the imperialists.