come upon
 碰見,偶然遇到,襲擊,攻擊
 come upon
      v 1: find unexpectedly; "the archeologists chanced upon an old
           tomb"; "she struck a goldmine"; "The hikers finally
           struck the main path to the lake" [syn: fall upon, strike,
            light upon, chance upon, come across, chance on,
            happen upon, attain, discover]
      2: take possession of; "She entered upon the estate of her rich
         relatives" [syn: enter upon, luck into]