It takes twice as much effort to breathe during sleep because of greater resistance to airflow in the airways and changes in the efficiency of the muscles used for breathing.

由于睡眠时呼吸道中的气流阻力更大，并且用于呼吸的肌肉效率有变化，所以在睡眠时呼吸需要用两倍的力气。

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Our ears were once used for breathing.

我们的耳朵曾经用来呼吸。

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Lung:Eitherof two light, spongy, elastic organs inthechest, used for Breathing.

肺：胸腔里两个轻软的，海绵状的，有弹性的器官组织，用于呼吸。

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It does this by stopping the muscles used for breathing.

VOA: special.2010.03.09

And traditional CPR should be used for any victims of drowning or collapse from breathing problems.

VOA: special.2009.06.09

Many other drugs could be used. For example, doctors say breathing oxygen also can help.

VOA: special.2010.03.30

Hiccups are sudden contractions of the muscles used for breathing in.

BBC: Why we hiccup

In addition to their show of splashing around the surface of the water, the humpbacks enchant visitors as their cries echo below the water, conducting a beautiful symphony for divers used to listening to just the sound of their own breathing.

BBC: Colombia��s prison turned paradise

The result will be a welcome glimmer of hope for under-pressure Reds manager Roy Hodgson, who used the breathing space of his team being top of their group ahead of the game to field a team mostly of youngsters and fringe players.

BBC: Napoli 0-0 Liverpool