Vowels and consonants

Vowel systems

British English is analyzed as having three sets of vowels:

• short vowels
• closing diphthongs
• centering diphthongs

Short vowels

FRONT  SPREAD  ROUND
   HIGH   /i/            /u/
   MID    /e/    /@/     /o/
   LOW    /a/            /^/

Closing diphthongs

FRONT   ROUND
   HIGH  /iy/     /uw/
   MID   /ey/     /ow/
   LOW   /ay/     /aw/

         /oy/     /iw/

Centering diphthongs

FRONT  SPREAD  ROUND
   HIGH   /ir/            /ur/
   MID    /er/    /@r/    /or/
   LOW            /ar/

The following macros are used to define vocalic place of articulation:

FRONT  := [voc:[-grv, -rnd]].
   SPREAD := [voc:[+grv, -rnd]].
   ROUND  := [voc:[+grv, +rnd]].

   HIGH := [voc:[height=close]].
   MID  := [voc:[height=mid]].
   LOW  := [voc:[height=open]].

In the lexicon, seven vowels and three off-glides are defined

Vowels

vow:[FRONT, HIGH] --> "i".
   vow:[FRONT, MID] --> "e".
   vow:[LOW] --> "a".

   vow:[-stressed, SPREAD, MID] --> "@"

   vow:[ROUND, HIGH] --> "u".
   vow:[ROUND, MID] --> "o".
   vow:[ROUND, LOW] --> "^".

Off-glides

cons:[-coda, FRONT, HIGH, GLIDE] --> "y".
   cons:[-coda, MID, GLIDE] --> "r".
   cons:[-coda, ROUND, HIGH, GLIDE] --> "w".

Note: off-glides are modelled as consonants which cannot appear in coda position, but which can appear in onsets and as off-glide in a nucleus.

Phrase structure rules

Nu:[-long] --> vow.   % short vowels

   Nu:[+long] -->        % closing diphthongs
     (vow:[voc:[grv=A, rnd=B]] \ 
      cons:[-coda, GLIDE, voc:[grv=A, rnd=B, height=close]]).
   Nu:[+long] -->        % /oy/
     (vow:[ROUND, MID] \ cons:[-coda, FRONT, GLIDE]).
   Nu:[+long] -->        % /iw/
     (vow:[FRONT, HIGH] \ cons:[-coda, BACK, GLIDE]).

   Nu:[+long] -->        % centering diphthongs
     (vow \ cons:[-coda, MID, GLIDE]).

Consonants

Consonants are defined as having a consonantal (primary) as well as a vocalic (secondary) place of articulation:

Feature definition

cons => cnt, son, voi, nas, str, cns, voc. 
   cns => grv, cmp.
   voc => grv, height, rnd.

The vocalic place of articulation for most consonants is acquired through feature spreading (see: Phonological and phonetic coarticulation).

Macro's are used to eliminate redundancy in the definition of consonants:

LABIAL   := [cns:[+grv, -cmp]].
   ALVEOLAR := [cns:[-grv, -cmp]].
   PALATAL  := [cns:[-grv, +cmp]].
   VELAR    := [cns:[+grv, +cmp]].

   STOP      := [-cnt, -son, -str, -nas].
   AFFRICATE := [-cnt, -son, -nas, +str].
   FRICATIVE := [+cnt, -son, -nas].
   ASPIRATE  := [+cnt, -son, -voi, -nas, +str, VELAR].
   NASAL     := [-cnt, +son, +voi, +nas].
   GLIDE     := [+cnt, +son, +voi, -nas, -str].

Examples

c:[-voi, LABIAL, STOP] --> "p".
   c:[-voi, ALVEOLAR, STOP] --> "t".
   c:[-voi, VELAR, STOP] --> "k".

   c:[+voi, LABIAL, STOP] --> "b".
   c:[+voi, ALVEOLAR, STOP] --> "d".
   c:[+voi, VELAR, STOP] --> "g".