In
addition to assimilation (feature-changing) and feature-addition rules,
phonological rules can delete or add entrie phonemic segments. In French, for
example, as demonstrated by Sanford Schane,5 word-final consonants are deleted
when the following word begins with a consonant (oral nasal) or a liquid, but
are kept when the following word begins with a vowel or a glide. (Note that in
French, /r/ operates as a liquid but not as a glide.)
Table
7.6 represent a general rule in French applying to all word-final consonants.
We distinguished these four classes of sounds by the nasal consonants and
liquids were specified as [+ consonantal], and vowels and glides as [-
consonantal]. We can now why such ‘super classes’ or ‘cover features’ are
important. Using the symbol O/ to represent the ‘null’ unit (or zero) and # as
‘word boundary’, we can state the French rule simply as :
In
Schane’s complete analysis, many words that are pronounced with a final
consonant actually have a vowel as their word-final segment in phonemic
representation. The vowel prevents the rule of word-final consonant deletion
from applying. The vowel itself is deleted by another, later rule. Given this
rule in the grammar of French, petit would be phonemically /pəti/,
because the rule determines the phonemic shape of the word.
Detection rules also show up as optional rules in fast
speech or casual speech in English. They result, for example, in the common
contractions changing he is [hi iz] to he’s [hiz] or i will [ai wɪl] to I’ll [aɪl].
In ordinary everyday speech most of us also delete the unstressed vowels that
are shown in bold type in words such as the following :
mystery
general
memory
funeral
vigorous
Barbara
These words in causal speech sound as if they were
written as follows :
mystry
genral
memry
funral
vigrous
Babra
Phonological rules therefore can be either optional or
obligatory. Phonological rules may also insert consonants or vowels, which is
called epenthesis. In some cases, epenthesis occurs to ‘fix up’ non-permitted
sequences. In English morphemes, nasal/non-nasal consonant clusters must be
homorganic, both labial, both alveolar, or both velar. We find /m/ before /p/
and /b/ as in ample and amble; /n/ before /t/ and /d/, gentle and gender; and /ŋ/
before /k/ and /g/, ankle and angle. (You may not have realised that the nasal
in the last two words has a velar articulation because the spelling can obscure
this fact. If you pronounce these words carefully, you will see that the back
of your tongue touches the velum in the articulation of both the n and the k.)
/m/ before /t, d, k, g/ does not occur morpheme internally; nor does /n/ before
/p, b, k, g/ nor /ŋ/ before /p, b, t, d/. With an epenthetic [p] as if it were
written Frompkin. She also receives letters addressed in this way.
This same process of epenthesis occured in the history
of English. The earlier form of the word empty had no p. Similarly a /d/ was
inserted in the word ganra giving us the modern gander.
In the history of Spanish, many words that now start
with an e followed by an [s] followed by another consonant came from Latin
words that were not vowel initial. For example, the Spanish word escribir, ‘to
write’, was scribere in Latin (the sc representing /sk/), and the Spanish word
for ‘school’, escuela, comes from the Latin word schola through epenthesis.
