再也没有洁净的白雪飘落，从天上落下来的只有被毒素污染过的冷雨。
Pristine snow no longer fell, only a cold rain tainted by toxins.
就算空气没有被污染，雨水也是呈弱酸性的，因为大气中的二氧化碳和其他酸性的气体会溶解在（雨）水中。
Rain is slightly acidic even in unpolluted air, because carbon dioxide in the atmosphere and other natural acid-forming gases dissolve in the water.
就算空气没有被污染，雨水也是呈弱酸性的，因为大气中的二氧化碳和其他酸性的气体会溶解在（雨）水中。
Rain is slightly acidic even in unpolluted air, because carbon dioxide in the atmosphere and other natural acid-forming gases dissolve in the water.
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