To their great disappointment, the scientists found that the solution to the problem they had been attempting at all these ten years turned out to be a blind alley.
使科学家们十分失望的是，十年来他们一直试图寻找解决那个问题的方法竟不奏效。
2
He has been trying to solve his money problem, but he is in a blind alley.
他一直尝试解决他金钱上的问题，但走进了死胡同。
3
He thought that the problem was one of thawing and that it might be a blind alley.