1. Phonology, part 4: Distinctive Features
March 13, 2012

2. Mid-term rehash! > 90: 10 80 - 89: 17 70 - 79: 13 60 - 69: 16
< 60: 14
Average: 71.9
High: 96.5
MT% = 2.6*QW
R2 = 22%

3. Natural Classes The same rules apply to /p/, /t/ and /k/. Why?
/p/, /t/ and /k/ form a natural class of sounds in English.
They are all voiceless stops
No other sound in English is a voiceless stop
A natural class is set of sounds in a language that:
share one or more (phonetic) features
to the exclusion of all other sounds in that language.
…and function together in phonological rules.
The phonetic “features” primarily include the phonetic labels we’ve already learned.
…although we’ll need to make some additions.

4. Natural Class Examples
For instance, in English:
[k], [g], form the natural class of velar stops
2. [u] and [o] form the natural class of rounded, tense vowels.
What natural classes are formed by the following groups of sounds?
[t], [s]
[v], , [z],
, ,

5. This is actually useful.
Phonological patterns are often formed by natural classes of sounds.
Ex: the (regular) English past tense exhibits allomorphy.
Allomorph 1: [d]
study  studied fear  feared
mail  mailed loan  loaned
Allomorph 2:
collect  collected mate  mated
wade  waded need  needed
What’s the natural class of segments that induces the change?

6. New Features
There are a few features in phonology that are more general than the ones we find in phonetics.
For instance: the Arabic Sun and Moon letters.
What’s the pattern?

7. New Features
The “Sun letters” include alveolars, post-alveolars and interdentals
= sounds made with the front part of the tongue
The “Moon letters” include everything else.
New feature: [CORONAL] is a cover term for alveolars, post-alveolars and interdentals.

8. Assimilation
The change undergone by the definite article in Arabic is called assimilation.
= when one sound becomes more similar to another in its environment.
In the Arabic case, there is complete, or total assimilation.
…but individual features can also change, as in place assimilation.
Ex: In English, /n/ often takes on the place of articulation of a following consonant.
‘unpleasant’
‘engrossed’

9. More Assimilation Remember this pattern? Plural forms: cat: dog:
match: judge:
chair: pass:
hose: puck:
The basic form of the plural is [z].
It exhibits voicing assimilation when following voiceless segments…
becoming voiceless [s].

10. More Assimilation Remember this pattern? Plural forms: cat: dog:
match: judge:
chair: pass:
hose: puck:
The basic form of the plural is [z].
It becomes when it follows [s], [z], or
These are [strident] consonants.

11. Some New Features Only CORONAL consonants can be [strident].
“strident” = noisy
Other place of articulation features:
LABIAL (involves the lips)
includes both bilabials and labio-dentals
[p], [b], [m], [f], [v]
DORSAL (involves the back of tongue)
includes both palatals and velars
[k], [g], [j]

12. Distinctive Features
The features used to describe natural classes of sounds in phonology are known as distinctive features.
…because they distinguish between otherwise identical sounds.
The distinctions made by features are (almost always) denoted by a [+] or [-] in front of the feature name.
For instance, stops and fricatives are distinguished by the feature [continuant].
[s] = [+continuant] (air flows steadily through mouth)
[t] = [-continuant] (air does not flow steadily through mouth)
(Note: nasals and affricates are also [-continuant])

13. Hitting Bottom
Distinctive features are considered to be the basic building blocks of language.
Sentences
Words
Morphemes
Phonemes
Features
The set of features is therefore universal.
The distinctive features determine:
What contrasts a sound makes with other sounds.
What natural classes a sound belongs to.

14. Feature Matrices
All of a phoneme’s feature specifications (+ or -) can be lumped together into a feature matrix.
For example: [t] =
Note: - is the default (unmarked) value.
Also note: there are complete feature matrices for all English sounds on pages 88 and 89 of the textbook.

15. Sub-Features, part 1
Note: the place features LABIAL, CORONAL, DORSAL are special in that they are not preceded by either + or -
(the textbook puts a () before them)
Some features only apply when a particular place feature is also part of a sound’s feature matrix.
For instance: only CORONALS can be strident.
Also: [anterior] applies only to CORONALS.
Is the sound at or in front of the alveolar ridge?
Yes: [+anterior] = interdentals, alveolars
No: [-anterior] = post-alveolars (=posterior)

16. Sub-Features, part 2 A sub-feature for LABIAL is ROUND.
= are the lips rounded?
All rounded vowels are [LABIAL]
…and all rounded vowels are [+round]
However: LABIAL consonants in English are [-round]
…with the exception of [w], which is [+round]

17. Sub-Features, part 3 DORSAL has the following sub-features:
[+back] vowels are (phonetically) back….
[-back] vowels are (phonetically) front.
Also: palatal consonants ([j]) are [-back];
Velar consonants ([k], [g]) are [+back]
2. [high] distinguishes high and non-high vowels
3. [low] distinguishes low and non-low vowels
(mid vowels are [-high], [-low])
4. Tense vowels are [+tense], and lax vowels are [-tense]
is [+reduced]

18. More Major Features
Note: consonants and vowels are distinguished by [consonantal]
Two major classes of consonants are distinguished by the feature [sonorant]:
[+sonorant] segments resonate when they’re produced
they include vowels, glides, liquids and nasals
[-sonorant] segments include:
stops, fricatives and affricates
these sounds obstruct the flow of air in the mouth
= “obstruents”
In English, only sonorants can be [+syllabic]

19. Laryngeal Features
Voiced and voiceless segments are distinguished by [voice]
Aspirated consonants are [+spread glottis]
also: [h]
And “glottalized” consonants are [+constricted glottis]
this includes the “glottal stop”
….but otherwise you can ignore this one.
Finally: affricates are distinguished from fricatives by [delayed release]
Affricates = [+delayed release]
Fricatives = [-delayed release]

20. Just for fun: Voice Quality
There are three primary types of vocal fold vibration:
modal
vocal folds lightly adducted; flow of air causes periodic opening and closing of folds
breathy
vocal folds slightly apart; flow of air makes folds “wave” in the wind
Breathy voice is [+voice], [+spread glottis]
3. creaky
vocal folds tensely adducted; low airflow causes irregular, low frequency voicing
Creaky voice is [+voice], [+constricted glottis]

21. The point of it all
Phonological rules can (and should) always be expressed in terms of distinctive features.
For instance, voicing assimilation (for English plurals):
[+voice]  [-voice] / [-voice] ____
[+continuant]
[CORONAL]
[+strident]
Let’s try our hand at a few of these…