In very severe cases, it can even defile some common objects, and in those cases, the source of impurity might have to be isolated or excluded if necessary.

在一些非常严峻的情况中，它会玷污一些普通的事物，在这种时候，不洁之源,也许只能被孤立，严重的话需要驱逐。

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Prolonged separation from family and friends back home is a huge source of stress for people in isolated, confined environments, Palinkas said.

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This energy source remains largely untapped, though, simmering either too far below the surface to reach, or isolated from water that could carry it up.

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