2.6 Phonological Rules
We learned about how English speakers will aspirate some phonemes. Is this a random act or can we figure out a pattern in this type of production? When considered carefully, we can notice that we only do it with /p/, /t/ and /k/. In addition, this only happens when these phonemes appear at the beginning of a syllable. When linguists figure out such a pattern, they can formally write it as a phonological rule. Generally, phonological rules map between two levels of representation: phonemes and phones (Goldsmith, 1995). Such rules define how we go from the abstract representation of phonemes in our mind to the actual articulation of phones. They start with an underlying representation (the string of phonemes) and produce a surface form (what is actually said).
The rule for aspiration in English could be stated as “All unvoiced stops will be aspirated when they appear as the onset of a syllable.” Each language varies in how phonological rules are applied and in hat circumstances they appear. For example, Germans will devoice (remove the voicing) of an obstruent if it appears as the coda of a syllable. So, they may pronounce ‘hund’ as [hʊnt] devoicing the [d] to a [t].
Living Language
Consider how to pronounce the /t/ when it appears between two vowels as in ‘butter’ or ‘notable.’ You will notice that most people in North America will not produce a hard [t] sound but a flap consonant [ɾ]. So /bʌtɚ/ becomes [bʌɾɚ] (the [ɚ] is a vowel with a rhotic or ‘r’ quality).
What other examples can you think of in how you make systematic changes to phonemes when you speak?
A formal way of expressing phonological and morphological processes of sound change.