endeavor做名詞時意為：努力；嘗試；任務.可數名詞
單一的努力用單數
1.Hard endeavor of 15 years is about to turn China's entry to the WTO into a reality .
經過15年的艱辛努力,中國加入世貿組織即將成為現實.
多種、多項努力用復數
Most of my endeavors are in collaboration with my wife, Jane Gray Morrison, and with colleagues and teams of researchers in dozens of countries.