Thing is that it's very difficult to classify.

问题是很难进行分类。

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Fossil finds are notoriously difficult to classify—people disagree on which physiological features are important; and each new find represents a class of one.

对化石发现进行分类是出了名的难——对于各种生理特性重要程度的判定可谓众口难调，而且一有新发现便会编入一个新的分类单位。

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It is therefore a construction which integrates very different needs and develops diverse proposals, which makes it difficult to classify it into a specific architectural typology or type of project.

由于该项目集不同需求于一体，还同时运用了不同设计方案，使得它很难被归类到一个特定的建筑类型或者项目类型中。

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