The origin of life is one of the great unsolved problems of science.

生命起源问题是科学上最悬而未决的难题之一。

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He is stressed by the unsolved problems of his day and finds relief through forgetting about them.

白天的工作中，有些问题还没有解决。他想暂时忘记它们，获得轻松的感觉。

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Items that are left broken and unfixed may be symbolic of "broken" things or unsolved problems in your life.

留着损坏了的东西而不把它修好，可能就是你生活中产生坏事和没有解决好问题的象征。

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Problems like the artificial heart are still unsolved, there's still room for innovation, still room to learn from what hasn't worked before, to learn from science, and to design something better.

人工心脏技术中存在的问题还没有解决,还有创新发展的空间,仍有从未涉足的领域来研究,通过对科学原理的学以致用,去设计出更好的产品

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There are numerous unsolved problems with the material, though, as this science blog, among many others, explains.

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They should identify unsolved problems, map the wider system influencing results, and determine weak links to strengthen or gaps to fill.

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Play permits the child to resolve in symbolic form unsolved problems of the past and to cope directly or symbolically with present concerns.

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