The sound of his breathing told her (that) he was asleep.

她从他呼吸的声音中听出来他睡着了。

《牛津词典》

They could hear each other's distressed breathing now, which showed them that the more terrible sound had passed.

他们现在能听到彼此紧张的呼吸声，这说明更可怕的声音已经过去了。

youdao

The only sound to be heard is their somewhat heavy breathing.

唯一能听到的声音是他们有点沉重的呼吸声。

youdao

Last weekend, everyone in my house heard what sounded like a deep breathing sound in our kitchen.

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Pieces were built around keyboard tones, flute, guitar noises, the sound of breathing, and occasional stretches of drumming.

NEWYORKER: Sound Machine

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.

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