天然洞体不稳定是绝对的，稳定是相对的。

The Instability of natural cave is absolute and its stability is relative.

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天然气补贴依旧是国库的无底洞。

Gas subsidies remain a heavy drain on the public purse.

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这些天然冰雕式样繁多，结构奇特，其中包括一种最为神奇的“瑞士干酪”冰山，这种冰山看起来就像是被钻出了许多的深洞，有些洞穴甚至形成了巨大的冰室。

The vast array of frozen sculptures includes 'Swiss cheese' icebergs which appear to have deep holes drilled into them and some that have formed gigantic cathedrals of ice.

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