ABSTRACT
It is the task of phonology to provide a formal representation of the phonic matter pertaining to the systems of natural languages. Typically, there are predictable, alongside unpredictable, aspects to such matter. Consider, for instance, the voice alternations induced by the suffix -th in English: five ~ fifth, twelve ~ twelfth (also hundre[t]th, thousan[t]th). Such contextual changes in the make-up of morphemes are of course formalised by means of phonological rules, which constitute the stock-in-trade of phonology.
