be-all and end-all

• 1.  

  PHRASE（习语） If something is the be-all and end-all to you, it is the only important thing in your life, or the only important feature of a particular activity. 一切的一切; 特定活动唯一重要的特征

  例：

  For some people, competing is the be-all and end-all of their running.

  对于一些人来说，跑步的全部意义就是比赛。