你应该看到你的腹部扩张和收缩。

You should see your stomach expand and contract.

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岩浆湖如同在呼吸一般，有节奏的扩张收缩，起伏涨落，湖面高度每隔几分钟就会变化几米，引人注目又令人心生畏惧。

The lake seemed to breathe, expanding and contracting, rising and falling, its surface level changing several feet in a matter of minutes, spectacular and terrifying at once.

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瞳孔识别是一种观察眨眼频率和瞳孔扩张、收缩的方法。通常是事先录下视频然后再仔细观察分析。

Pupillometrics is a method of measuring blinking rates and pupil dilation or constriction, which can be done with video recordings and careful later analysis.

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