Tone unit
Tone unit is a stretch of speech uttered under a single coherent intonation contour. It tends to be marked by cues such as a pause and a shift upward in overall pitch level at its beginning, and a lengthening of its final syllable.
A tone-unit is a speech unit between pauses with its own features and structure. Each syllable of a tone-unit has a certain pitch and different degrees of prominence. A tone-unit normally consists of a prehead, head, nucleus and tail.
Prehead Head Nucleus Tail
Ex.: It was a 'very 'sunny ‘day yesterday.
The prehead comprises unstressed and stressed syllables preceding the first accented syllable.
The head is a part of a tone-unit that extends from the first accented syllable up to (but not including) the last accented syllable called the nucleus.
The nucleus is the most important part of the tone-unit as it carries the most significant information in a message and defines the communicative type of the sentence. It is the last stressed syllable of the last accented word in a tone-unit. A tone-unit may be deprived of all other elements but the nucleus is always present.
The tail comprises unstressed and stressed syllables that follow the nucleus.
Tone unit. (2019). StudFiles. Retrieved from: https://studfile.net/preview/9686417/
Tone unit. (2024). Oxford Learner’s Dictionaries. https://www.oxfordlearnersdictionaries.com/us/definition/english/tone-unit
Du Bois, J. W., Cumming, S., Schuetze-Coburn, S. & Paolino, D. (1992). Discourse Transcription, Santa Barbara Papers in Linguistics, 4, Department of Linguistics, University of California, Santa Barbara, CA.