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Phonetics Laboratory
Faculty of Linguistics, Philology, and Phonetics

Syllables and metrical feet

English syllable structure is assigned by the following (radically simplified) set of phrase structure rules (see also Coleman 1992):

Syl --> (On / Ri).

On --> (closure:[-nas] / cons:[GLIDE]).
On --> closure.
On --> cons:[GLIDE].

closure:[nas=A] -->
(cons:[-voi, +str, ALVEOLAR, FRICATIVE]
/ cons:[-cnt, -str, voi=A, nas=A]).
closure:[nas=A] --> cons:[-cnt, -str, nas=A].
closure --> cons:[FRICATIVE].

Ri:[heavy=A] --> (Nu:[branching=A] \ Co:[branching=A]).

Nu --> ...

Co --> (cons:[+coda, GLIDE] \ cons:[-son]).
Co --> (cons:[NASAL, cns=A] \ cons:[-son, cns=A]).
Co --> cons:[+coda].

Rules for the nucleus are presented elsewhere, as well as some of the necessary feature definitions (see: Vowels and consonants).

The following template is used to assure that branching nuclei and codae are marked as [+branching], whereas non-branching nodes are left unspecified for this feature:

[+branching] --> [], [].

Also, templates are used to assign the features heavy and stress the status of head-features:

[heavy=A, stress=B] --> ([] / [heavy=A, stress=B]).
[heavy=A, stress=B] --> ([heavy=A, stress=B] \ []).
[heavy=A, stress=B] --> [heavy=A, stress=B].

As a result, a syllable is marked as [+heavy] if the nucleus or the coda branches. Otherwise, a syllable is left unspecified for this feature.

Syllables are grouped into metrical feet by rules such as the following, which assure that heavy syllables are analyzed as the head of a foot.

Foot --> 
((Syl:[+stress] \ Syl:[-heavy, -stress]) \ Syl:[-heavy, -stress]).
Foot -->
(Syl:[+stress] \ Syl:[-heavy, -stress]).
Foot --> Syl:[+stress].

Note, however, that the above rules do not represent a fully developed analysis of English word stress.