exhalation       
noun [ C or U ]  formal uk/ˌeks.həˈleɪ.ʃən/ us/ˌeks.həˈleɪ.ʃən/
 呼气
the action of sending air out of your lungs
  With a short exhalation, he prepared for the work ahead. 短短地呼了一口气,他为下一步工作做起了准备。 
 You could hear every ragged exhalation.  你可以听到每一个粗重的呼气声。 
 See: exhale
 - More examples
 - The scans produced an image of each patient's lungs after exhalation.
 - I could hear her breathing next to me, and felt a faint exhalation.
 - She amused herself by varying the rhythm of her exhalations.