LECTURE_4_English consonants

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ENGLISH
CONSONANTS
• We have seen how the vowels of languages can be
described in terms of values on a small number of
dimensions, or equivalently, features. In this section
we will see that the same holds true for consonants.
Languages vary a great deal with respect to how
many vowel and consonant phonemes they have, but
all languages seem to have more consonants than
vowel phonemes. Not surprisingly, more consonant
dimensions than vowel dimensions are contrastive for
languages.
POA
• Some cons. are produced with a complete closure of the vocal tract,
blocking the passage of air. Consonants made by completely
closing the vocal tract are called stops. As we discussed informally,
different consonants can be produced by varying the place where
the closure occurs. This consonant dimension is known as place of
articulation; we will see later that the place of articulation is also
relevant when there isn't a complete closure of the vocal tract. In
one sense place of articulation has six different dimensions
because it involves independent movement of six separate parts of
the vocal tract. Each of these structures is called an articulator.
The articulators relevant for place of articulation are the lips, the
tongue tip, the tongue body, the tongue root, the pharynx (the
region behind and below the oral cavity), and the glottis (the gap
between the vocal cords). Each language makes use of several
places of articulation, usually between three and six, to distinguish
its consonant phonemes. In this section, we'll only consider those
places that are relevant for English.
LIPS
• There are two possible places of articulation involving
the lips as articulators. For bilabial place of
articulation, the lips are brought together (or for nonstops, as we'll see later, close together). The first and
last consonants in the word bib are bilabial stops.
The symbol for this consonant is /b/, so the
pronunciation of bib is written /bɪb/. A further possible
position of the lips is contact between the lips and
upper teeth; this is not used for English stops, though
it is used for other English consonants. It is discussed
below.
TEETH
• With one part or another of the tongue as articulator,
there is a continuous range of possible places for contact
with the roof of the mouth, beginning with the upper teeth
and extending back to the uvula at the back of the
mouth. All languages apparently make use of at least
two positions within this range. For English stops, two
positions are relevant. One of these is contact between
the tip of the tongue and the ridge that is just behind the
upper teeth, the alveolar ridge. This is referred to as
alveolar place of articulation. It is a feature of the first
and last consonants in the word did. The symbol for
these stops is /d/, so the pronunciation of the word did is
written /dɪd/. The configuration of the vocal tract for the
pronunciation of /d/ is shown in the figure below.
VELUM
• There is a further possibility for contact between the
tongue and the roof of the mouth that is used in most
languages. The back of the tongue body contacts the
region near the back of the roof of the mouth, near
the structure called the velum. This is called velar
place of articulation. It is a feature of the first and last
consonants in the word gag. the symbol for these
stops is /g/, so the pronunciation of gag is written
/gæg/. The position of the vocal tract for the
pronunciation of /g/ is shown in the figure below.
• So English distinguishes the stops /b, d, g/ along the
dimension of place of articulation. Other places of
articulation are utilized for other English consonants that
are not stops and for consonants in other languages.
• Now notice what these three stops share. Like all stops,
they are produced with complete contact between the
articulators. In addition, all of them are accompanied by
voicing, that is, vibration of the vocal cords, during the
contact. Thus when they appear at the beginning of a
word, the voicing starts before the contact is released
(and continues through the following vowel), and when
they appear at the end of a word, the voicing continues
after the contact is made. (Note that the voicing can't
start too much before the beginning of a word like bib or
stop too much after the end of a word like bib because
the air being passed through the vocal cords can't
escape, and pressure builds up quickly behind the point
of contact, preventing more air from being expelled from
the lungs. You can verify this for yourself by trying to
pronounce a long /b/, /d/, or /g/ sound without releasing
the contact between the articulators.)
VOICING
• But this is not the only possibility for how the
voicing and the beginning and end of the contact
can be timed. When the stop consonant comes
at the beginning of the word, we get a different
effect when the voicing begins after the release
of the contact; listen to the difference between
the words bay and pay. Similarly at the end of
the word, the effect is different if the voicing
ends before the contact or roughly at the same
time as the contact; compare add and at. The
dimension that distinguishes these pairs of
words from each other is called voicing. For the
moment we will consider only two values for this
dimension — voiced and voiceless — but, as
we will see later, voicing is actually more
complicated than this.
• Just as English has voiced stops at the bilabial, alveolar, and
velar places of articulation, it also has voiceless stops at these
places. The voiceless bilabial stop is illustrated at the beginning
and end of the word pep. It is symbolized with /p/, so the
pronunciation of pep is written /pεp/. The voiceless alveolar
stop is illustrated at the beginning and end of the word tot. It is
symbolized with /t/, so the pronunciation of tot is written /tͻt/.
The voiceless velar stop is illustrated at the beginning and end
of the word kick. It is symbolized with /k/, so the pronunciation
of kick is written /kɪk/. There is also a voiceless stop with its
place of articulation at the glottis; this is referred to as glottal
place of articulation. For a glottal stop, the vocal cords are
brought together, blocking the airstream as for other stops, and
then released suddenly. The glottal stop may appear at the
beginning of English words that begin with a vowel, and it
appears in the middle of the word uh-oh. It is not normally
considered an English phoneme, however, because it is not
used to create new English words or to distinguish English
words from one another. The symbol for a glottal stop in this
book is /ʔ/ (the IPA symbol is like a question mark with no dot at
the bottom), so the pronunciation of uh-oh is written /ʔ^ʔͻ/.
MOA
• So far all of the consonants we have looked at have involved a complete
closure of the vocal tract, blocking air from passing out. But this is not
the only way to make consonants. In fact we need a new dimension for
the various possibilities (really a whole cluster of dimensions); this is
called manner of articulation. One crucial variable within manner of
articulation is the distance between the articulators. For stops, the
closure is complete, but there are two further possibilities. One,
discussed in this subsection, involves a narrow, but not complete,
closure that allows air to pass through the aperture but with
accompanying noise. The other, discussed in the next subsection,
involves an opening that is wide enough for the air to pass through
unimpeded. Stops and fricatives are different manners of articulation.
Consider what happens when you bite your lower lip with your upper
teeth and then blow air out. Unless you're biting too hard, some of the air
can pass between your teeth and lip, creating a sound like that at the
beginning and end of the word fife. A phone made like this, with an
incomplete or approximate closure that permits air to pass through and
produces a noisy sound due to the resulting turbulence, is called a
fricative. The fricative at the beginning and end of the word fife is
voiceless because the fricative sound is not accompanied by voicing.
That is, the voicing starts after the vocal tract is opened up for the vowel
and stops just before the closure made again at the end of the word.
LABIODENTALS
• The place of articulation for this consonant is one we
didn't encounter for English stops; it is the second of
the possible places associated with the lips (in
addition to bilabial place of articulation). It is called
labiodental place of articulation. The symbol for the
voiceless labiodental fricative is /f/, so the
pronunciation of the word fife is written /faıf/. English
also has a phoneme that is the same as /f/, but
voiced. This is the sound at the beginning and end of
the word verve. It is symbolized by /v/, so the
pronunciation of verve is written /vз:v/.
DENTALS
• English has a pair of fricatives at another place of
articulation where there are no English stops. Try putting
your tongue between your teeth or against the back of
your upper teeth and then expelling air from your mouth.
Again if the contact is not too tight, some air should pass
between your tongue and your teeth, generating
turbulence that results in the consonant that appears at
the beginning of the word thing and at the end of the
word both. The place of articulation for this consonant is
called dental place of articulation. The symbol for the
voiceless dental fricative is /θ/, so the pronunciation of
the word both is written /boθ/. English also has the
corresponding voiced phoneme; it is the initial consonant
in the word this and the final consonant in the word
bathe. It is symbolized by /ð/ in this book, so the
pronunciation of bathe is written /beð/.
FRICATIVES
• Although English has no bilabial fricatives, it
does have alveolar fricatives. When the
tongue is allowed to approach but not quite
come in contact with the alveolar ridge, we
get the consonants in the word sauce if it is
not accompanied by voice and the
consonants in the word zoos if it is
accompanied by voice. The symbols for these
alveolar fricatives are /s/ and /z/, so the
pronunciation of sauce is written /sͻ:s/, and
the pronunciation of zoos is written /zu :z/
PALATO-ALVEOLAR
• Somewhat behind the alveolar ridge, it is possible to
bring part of the body of the tongue near the roof of
the mouth and produce voiceless and voiced
fricatives that are distinguishable from /s/ and /z/. The
voiceless fricative appears at the beginning and end
of the word shush. It is symbolized by /ʃ/, so the
pronunciation of shush is written / ʃ ۸ ʃ /. The voiced
fricative at this place of articulation is a somewhat
marginal phoneme in English, and it does not
normally appear at the beginnings of words. It is the
consonant in the middle of the word Asia. The symbol
for this consonant in this book is /Ʒ/ (somewhat like
the IPA symbol), so the pronunciation of Asia is
written /eıƷə/. / ʃ / and /Ʒ/ are produced at what is
called the postalveolar place of articulation.
GLOTTAL FRICATIVE
• English does not have velar fricatives,
but it does have a voiceless glottal
fricative, produced by making the glottis
narrow enough for a breathy sound to
be created. This is the consonant at the
beginning of the word hot; this phoneme
does not occur at the end of English
words. It is symbolized by /h/, so the
pronunciation of hot is written /hͻt/
AFFRICATES
• We have seen that stops involve complete closure, and
fricatives involve approximate closure. It is also possible
to combine these two by beginning with a complete
(stop) closure and ending with an approximate (fricative)
closure. Such phones are called affricates. English has
two of them, voiced and voiceless affricates produced at
the postalveolar place of articulation. The voiceless
postalveolar affricate is the first and last consonant in the
word church; it is symbolized by /tʃ/ in this book, so the
pronunciation of church is written / tʃ ə: tʃ /. The voiced
postalveolar affricate is the first and last consonant in the
word judge; it is symbolized by /ʤ/ in this book, so the
pronunciation of judge is written / ʤ ۸ʤ /.
NASALS
•
Pronounce the syllable /ba/ while holding your nose. Now try the same thing,
replacing the /b/ with an "m" sound (as in mama). What can you conclude about
the difference between /b/ and the sound of "m"? The the same thing with /d/ and
the sound of "n". Also try to pronounce the word sing while holding your nose, and
notice what happens to the final consonant (written with the letter combination
"ng"). English nasal and lateral consonants have a complete stop-like contact in
one place, but the air escapes somewhere else. One way to produce a sonorant
consonant is to completely close the oral cavity, just as for a stop, but to open up
the nasal cavity, the empty region behind the nostrils and above the oral cavity.
This is achieved by lowering the velum, the flap at the back of the roof of the
mouth. The nasal cavity and velum are shown in the figure below, in which the
vocal tract is configured for the production of the sound at the beginning and end of
the word mom. Such phones are called nasal consonants. For nasal consonants,
the air is allowed to pass through the nasal cavity, but it also resonates in the oral
cavity, and the place of articulation (within the oral cavity) distinguishes different
nasal consonants from one another. English has three nasal consonant phonemes,
at the bilabial, alveolar, and velar places of articulation. The bilabial nasal is the
one at the beginning and end of the word mom; it is symbolized by /m/, so the
pronunciation of mom is written /mͻm/. The alveolar nasal is the one at the
beginning and end of the word none; it is symbolized by /n/, so the pronunciation of
none is written /n^n/. The velar nasal is the one at the end of the word sing (this
phoneme does not appear at the beginning of words in English); it is symbolized in
this book by /ŋ/, which is close to the IPA symbol, so the pronunciation of sing is
written /sɪŋ/.
APPROXIMANTS
• The other way to produce a sonorant is to leave an opening in
the oral cavity that is wide enough so that there is none of the
noise that characterizes fricatives. These consonsants are
called approximants because the approach of the articulators
is only approximate. One way to achieve this is to make a
complete contact as for a stop consonant but release the air at
one or both sides of the tongue. Such a sound is called a lateral
approximant. English has one lateral approximant phoneme,
with the contact at the alveolar place of articulation. This is the
sound at the beginning and end of the word lull; it is symbolized
with /l/, so the pronunciation of the word lull is written /lʌl/.
RETROFLEX
• A further possibility is for no closure of the oral cavity
at all. English has three such consonants. One is
produced with the tip of the tongue curled somewhat
back and approaching the roof of the mouth behind
the alveolar ridge. This is the sound at the beginning
and end of the word rear . We will use the symbol /r/
for this consonant (though the more precise IPA
symbol is [ɹ]; [r] is often used for an alveolar trill or
tap). Sounds produced with the tongue curved in this
way are called retroflex; we can treat this as a
particular place of articulation (though not everyone
does).
• The two other approximants are produced similarly to high vowels,
except that the articulators are usually not brought as close together
as they would be for vowels. One of these consonants approaches
the vowels /u/ and /ʊ/. It is the consonant found at the beginning of
the word we and is symbolized by /w/, so the pronunciation of we is
written /wi:/. Note that this phoneme has two simultaneous places of
articulation: velar, because the back of the tongue approaches the
velar region, just as for /u/, and bilabial, because the lips are rounded
and brought close together, as for /u/. The other English approximant
resembles the vowels /i/ and /ɪ/. It is the consonant found at the
beginning of the word you and is symbolized by /j/, so the
pronunciation of you is written / ju:/. (Note that in IPA, this consonant
is symbolized by /j/.) The place of articulation for this consonant is
one we haven't seen yet for any consonants; as for the vowel /i/, the
middle of the tongue approaches the region in the middle of the roof
of the mouth. This is referred to as the palatal place of articulation.
• It should be clear by now that the distinction
between vowels and consonants is really a
matter of degree. The consonants that are the
least vowel-like are stops, which involve a
complete closure of the vocal tract and cannot
be pronounced continuously. A little more like
vowels are fricatives, which can be pronounced
continuously but which still have the
characteristic fricative noise resulting from the
narrow opening in the vocal tract. Closest to
vowels are sonorants. All of these can be
pronounced continously.
SEMI-VOWELS
• The phones /w/ and /j/ are the closest of all to vowels.
Each has a place and manner of articulation very
similar to a high vowel.
• Because of their similarity to "true vowels", [w] and [y]
are sometimes called semivowels. For our purposes
(and maybe for anyone's purposes) there will be no
point to arguing about whether semivowels are
vowels or consonants. When we emphasize their
consonant properties, we will speak of them as
consonants; when we emphasize their vowel
properties, we will speak of them as vowels.
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
/p/ pin, spin, lap
/b/ bin, lab
/m/ man, ham
/f/ fin, if
/v/ vine, live
/θ/ thin, both, ether
/ð/ this, bathe, either
/t/ talked, stone, lit,
/d/ den, lid, hugged
/s/ sin, kiss, lips
/z/ zoo, easy, lose, eggs
/n/ pin, manner, listen
/l/ lip, sell, castle
/ʧ/ church, nature
/ʤ/ gene, jar, gradual
/ʃ/ shin, mission, nation, fish, machine
/Ʒ/ leisure, garage (for some speakers)
/r/ rip, narrow, year
/j/ year, cute /kyut/
/k/ kin, call, lick, chemical
/g/ get, anger, leg /ŋ/ sing, anger, anchor
/w/ witch, which, reward
/h/ hip /ʔ/ uh-oh /ʔ^ʔo/
Consonant clusters
• In English, more than one consonant
can
• come before or after a vowel
• CCVC stop, please
• CVCC post, desk
• CCCVC splash, spring
Consonant clusters in
English
Word-initial CC (except /s/-initial ones)
• pr pray pl play
• br bread bl bled
• tr try
• dr dry
• kr cream kl clear kw quick
• gr grow gl glow
• fr fry fl fly
• thr throw
• shr shrimp
Phonotactics of initial CCs
• Constraints on what comes where in English
• consonant clusters
• In CCs, the first position is always taken by
p,
• t, k, b, d, g or s, f, sh, or th
• The second position is always taken by l, r, w
• or j (except when the initial consonant is s
Further generalizations
• In terms of their phonetic qualities, the consonants
• that can occupy different positions in the cluster
• tend to form ‘phonetic classes’
• First position
• p, t, k, b, d, g: stops (voiced and voiceless)
• f, s, th, sh: voiceless fricatives
• Second position
• l, r: liquids
• w,j: glides
Stops
Fricatives
Liquids and glides
•
•
•
•
•
•
•
S-initial CCs and
split spring CCCs spurious
speak
Stand
*
string
stew
sky
schlerosis scream square Skew
sleep
*
small
*
snail
*
swan
*
Phonotactics of s-initial
CCs
•
•
•
•
•
•
•
•
In two consonant clusters:
/s/ is followed by:
p, t, k: voiceless stops
m, n: nasals
l, w: liquids and glides
In three-consonant clusters:
the second position is a voiceless stop: p, t, k
the third position is a liquid: I, r
Quick exercise:
syllable structure
Show the syllable structure of the following
words, using V for vowel and C for Consonant
• green
CCVC
play
• them
stress
• ask
friend
• see
not
• eggs
at
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