现在，这样的速度是很不寻常的，比冰川的正常移动速度快几百倍，但是你可以看到冰川在这些涌动中移动，虽然很少见。

Now, speeds like that are pretty unusual, hundreds of times faster than the regular movement of glaciers, but you can actually see glacier move during these surges, though it is rare.

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科学家们知道行星是从年轻的恒星周围的物质盘中形成的，但是理论认为从尘埃盘到行星系统的转变非常快，人们很少见到在这一阶段的物体。

Scientists know planets form out of the discs of material around young stars, but theory says the transition from dust disc to planetary system is rapid and few objects are caught during this phase.

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但是恰恰是一些个子不高的人会有很少见的基因突变，也就是“高寿基因”，它可以延长寿命。

Also, some shorter people possess a rare genetic mutation, known as the "Methuselah gene," that seems to extend their life spans.

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