Phoneme - Restrictions On Occurrence

Restrictions On Occurrence

Languages do not generally allow words or syllables to be built of any arbitrary sequences of phonemes; there are phonotactic restrictions on which sequences of phonemes are possible and in which environments certain phonemes can occur. Phonemes that are significantly limited by such restrictions may be called restricted phonemes. Examples of such restrictions in English include:

• /ŋ/, as in sing, occurs only at the end of a syllable, never at the beginning (in many other languages, such as Swahili or Thai, /ŋ/ can appear word-initially).
• /h/ occurs only before vowels and at the beginning of a syllable, never at the end (a few languages, such as Arabic, or Romanian allow /h/ syllable-finally).
• In many American dialects with the cot–caught merger, /ɔ/ occurs only before /r/ and /l/ (and in the diphthong if this is not interpreted as a single phoneme).
• In non-rhotic dialects, /r/ can only occur before a vowel, never at the end of a word or before a consonant.
• /w/ and /j/ occur only before a vowel, never at the end of a syllable (except in interpretations where a word like boy is analyzed as /bɔj/).

Some phonotactic restrictions can alternatively be analyzed as cases of neutralization. See Neutralization and archiphonemes below, particularly the example of the occurrence of the three English nasals before stops.