#Speech rhythm and utterance stress.
Rhythm - regularity or periodicity in the occurrence of a particular phenomenon in an utterance. In some languages the recurring phenomena are stresses, in others - syllables. So languages can be characterized either by stress-timed or syllable-timed rhythm. English is considered to be mostly a language with stress-timed rhythm (it presupposes that utterance stress serves as a basis for the rhythmical organization of speech and that stresses segment the speech continuum into units of more or less equal length. These are accentual or rhythmic units. Hierarchically higher are prosodic units: intonation groups and utterances. Rhythmic units form a certain hierarchy, since stresses, on which they are based, are not equal in their prominence, position and function. The most prominent and functionally more important is the nuclear stress. Therefore the nuclear rhythmic unit is the most important in an utterance. A rhythmic unit formed by full stress together with partial stress can be defined as a complex rhythmic unit.