ABSTRACT
The term prosody is often used as a cover term for the suprasegmental aspects of speech. Phoneticians recognize various degrees of stress, though for most purposes a simple distinction between stressed and unstressed is sufficient. Stress-timed languages tend to have a less even rhythm than syllable-timed ones, and often the strong rhythmic alternation between stressed and unstressed syllables in these languages results in a weakening of the unstressed syllables. The duration of segments is also considered to be one of the prosodie aspects of speech. In some languages, vowel length is a noncontrastive aspect of the sound system. The pitch of the voice is adjusted through the tension of the vocal folds. If their tension is increased, the vocal folds will vibrate more quickly. A variety of other systems are also often found, such as numerical marking of tone levels. Intonation is the linguistic use of pitch over groups of syllables, and signals syntactic and semantic information.
