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    1. cornerstone

      英 ['k??n?st??n] 美['k?rn?ston]
      • n. 基礎(chǔ);柱石;地基

      考試真題


      sustainable way is the cornerstone (基石) of our nation's energy security, and will be one of the major challengesof the 21st century.

      出自-2011年12月閱讀原文

      The college students had cultivated the ability to ask questions, the cornerstone of critical thinking.

      出自-2015年12月閱讀原文