unestablished [ˌʌnə'stæblɪʃt]

例句:

• Two old plutonium disposal plants damaged at once by some unestablished reason.
  两个遗留有钋的星球被一些不明原因突然破坏.
  
• So these loaded terms have an unestablished first cause which forever puts them outside the sphere of science.
  来自SA