你会感受到一个撑子(扩张器)，它可以保持你的眼睛睁开。

You will be aware of a support (speculum), which helps to hold your eye open.

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当宇宙扩张之时，星系的大小保持不变。

As the universe expands, these galaxies stay the same size.

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当宇宙扩张之时，星系的大小保持不变。

As the universe expands, these galaxies stay the same size.

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