Phonetics is the study of speech. It is concerned with how speech sounds can be categorised、how they are generated in the human vocal tract、why they each sound different to a listener、and how a listener is able to recognise them. The study of the organisation of speech sounds in a language is called phonology、while the study of how humans use their vocal apparatus to speak is called articulatory phonetics. The study of the quality of the sounds used to signal different pronunciations is called acoustic phonetics、while the study of how we perceive and decode speech sounds is sometimes called auditory phonetics. Finally、the general field of study in which instruments are used to study speech production and perception is called experimental phonetics
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