Unfortunately, the standard definition of a second relies on what the atom does at a temperature of absolute zero. Real clocks need to run at room temperature, where the shell of electrons puffs up.

遗憾的是，一秒钟的标准定义依赖于原子在绝对零度的条件，而实际的时钟需要在室温下运行，室温条件下电子壳层膨胀了。

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You can also pick a different room type, called "shell," like an island.

当然你也可以选择不同的房间风格，这种风格叫做“壳”比如，一个小岛。

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No sound comes from the shell, though there is plenty of air in the room.

虽然隔音房内有充足的空气，贝壳里却一片安静。

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Beneath the shell is room to insert a micro SD memory card.

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They spoke to retired Shell employees and spent two days--all they were allowed--in Shell's data room, scouring for updated information and digging through trash looking for signs of rival bidders.

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When it was all over, shell casings littered his front yard and seven bullet holes were scattered across his home, including one in his living room that left his television shattered.

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