By fossils, we mean traces of prehistoric animals such as bones, which become mineralized, or impressions of bones or organs that are left in stone.
我们所说的化石，指的是史前动物的遗迹，如已矿化的骨头，或留在石头上的骨头或器官的印痕。
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The chances of escaping complete destruction are vastly improved if the organism happens to have a mineralized skeleton and dies in a place where it can be quickly buried by sediment.