undefined [ˌʌndɪˈfaɪnd]

例句:

• Nowadays the dollar is undefined and unanchored.
  来自WSJ
• The money was lent for an undefined period of time.
  这笔钱无限期借出。
  
• The meeting of any person filled Nixon with an undefined dread.
  与任何生人的会见使尼克松充满了莫名其妙的紧张.
  
• He turned an expression of undefined appeal toward Scobie.
  他转向斯考比,脸上呈现出一种迷惘的祈求神色.
  
• Insert the generic undefined actor of your choice.
  来自SA
• The functions of the Governing Council remained undefined.
  来自NEWYORKER