uncertain

• The nature of these damping effects is uncertain .
  这些阻尼影响的性质是不定的。
• The chances of success are uncertain .
  成不成没准儿。
• Hiss seemed genuinely uncertain and confused .
  希斯看来已真的把握不定和心烦意乱了。
• Their marriage must be at a very uncertain distance .
  他们必须在很不确定的将来结婚。
• He was of uncertain temper .
  他的脾气时好时坏。
• The most uncertain link in the new allied chain was russia .
  新同盟体系最靠不住的是俄国。
• His whereabouts is uncertain .
  他目前下落不明。
• Peter's wide grin was wary and uncertain .
  彼得斯的开朗露齿的笑容是谨慎小心，难以捉摸的。
• Events in any real world are both complex and uncertain .
  任何现实社会里的事件都复杂多变。
• An uncertain but unceasing disquiet is upon me .
  不知道什么缘故，我始终觉得心里七上八下的。