(adj.) not easily solved; 'an apparantly insolvable problem'; 'public finance...had long presented problems unsolvable or at least unsolved'- C.L.Jones .
鲍里斯校对
双语例句
I pondered the mystery a minute or two; but finding it insolvable, and being certain it could not be of much moment, I dismissed, and soon forgot it. 夏洛蒂·勃朗特.简·爱.