When the drowning people's mouths are above the surface, they exhale and inhale quickly as their mouths start to sink below the surface of the water.

溺水者的嘴高于水面时，他们迅速地呼气和吸气，因为他们的嘴已开始沉下水面。

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Drowning people's mouths alternately sink below and reappear above the surface of the water.

溺水时人的嘴交替地沉没于水下或再出现于水面上。

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In a marsh, the surface water can sink slowly down through the soil into the rock below.

在沼泽地里，地表水会通过土壤慢慢地渗透到下面的岩层里。

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Typically, one will sink to 1, 500 or 2, 000 m below the surface and then drift for 10 days.

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