ToBI (/ˈtoʊbi/;[1] an abbreviation of tones and break indices) is a set of conventions for transcribing and annotating the prosody of speech.
Pitch accents, written as H* or L* (high and low tones, respectively), are typically realized on words that carry the most information in a sentence.
For example, the intonation at the end of a question might be H*L-H%, indicating that the pitch starts high, falls to a low, and rises again; or L*H-H%, indicating that the pitch starts low, then rises steadily to a high.
[8] Boundary tones, written with H% and L%, are affiliated not to words but to phrase edges.
The contrast between the statement and the question is signalled by a boundary tone at the end of the phrase: a low boundary tone causes a falling pitch contour, signalling the statement, whereas a high boundary tone causes a rising pitch contour, signalling the question.