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consonants ngu am am vi

2.1 How sound is produced
The ways in which we produce the sounds of any language is through
articulators, or organs of speech, as the diagrams below show:

Diagram 1 Articulators/Speech Organs

Consonants in English are pulmonic. That is, their formation depends upon an
egressive (outward-flowing) airstream initiating in the lungs. Pulmonic
consonants are described according to three features:


place of articulation;



manner of articulation;



whether the vocal cords vibrate in articulation that is if they are voiced.


Together, this is known as the voice-place-manner articulation or VPM
descriptors.


The IPA is designed to capture the sounds of all varieties of English. Table 1
below shows the consonants to be found in the English spoken in England as
they correspond to VPM descriptors.

2.2 Place of articulation
The column titles above refer to the place of articulation. Starting from the
left:


In producing bilabial consonants, both lips are involved, as exemplified in the
[m] of /mute/; such consonants restrict the airflow to a greater or lesser extent.
Labiodental articulation takes place when the top teeth and the bottom lip
come into contact, producing sounds such as [v] as in /vase/ and [f] found in
/face/.
Dental articulation is where the tongue may protrude between the teeth in
order to produce dental sounds, which in English are heard as /th/;
represented by phonemes [θ] found in /thing/ and [ðð̠] as in /those/.
Alveolar articulation or sounds is where sounds are produced when the blade
of the tongue is placed against the alveolar bridge; the bony platform right
behind the teeth. In English this includes sounds like [d] for instance in
/dance/, [z] as in /zoo/ and [n] found in /new/.
Post Alveolar articulation or consonants is where sounds are produced further
backwards, halfway between the alveolar ridge and hard palate. Articulation
of these consonants involves the body of the tongue being raised towards the
front of the palate. In English, these include [ ʃ ] and [ʒ], known respectively as
/sh/ and /zj/, for instance in /fish/ and /pleasure/.
Uvular and pharyngeal articulation is not found in English, but is present in
other languages and varieties of English.
Retroflex describes when consonants are articulated between the alveolar
ridge and hard palate with a tongue positioned in a backward or curled shape,
often with the tip raised. This curling back process involves the tip of the
tongue being placed in a position further back in the mouth; a key feature that
distinguishes these types of consonants from the alveolar ones which reflect
the same orthographic unit. Note though, that although retroflex consonants
are not found in RP English for example, they do occur in other English
accents, like Ulster Irish.


Palatal sounds are those which involve the body of the tongue rising towards
the most domed part of the palate. In English, the only palatal sound is [j]
which corresponds to the letter /y/, as shown in the word /yacht/.


Velar sounds (also known as velum) involve the back of the tongue moving
towards the soft palate that lies behind the palate itself (ref4). In English, three
velar phonemes exist, including [k] as in /kite/, [g] like in /gang/, and [ŋ]; the
latter sounds like, and is orthographically represented as /ng/, occurring at the
end of syllables, for instance in /dancing/.
Glottal sounds are produced by putting pressure on the airflow in the glottis
by closing and pivoting vocal cords. In English, two glottal sounds are present;
the glottal stop [ʔ] which replaces the /t/ phoneme in words such as /that/
found some accents like cockney, and the voiceless glottal fricative [h], whose
sound is indicated in words like /hat/.

2.3 Manner of articulation:
The row headings which make up the second main axis of the above chart
represent the manner of articulation.
The plosives, known to be the most consonantal of the manners of articulation
(ref5), involve completely closing the vocal tract at one of the points of
articulation; the pressure then builds up from the bottom and so an egressive
airstream is pushed out of the lungs into the oral cavity. This eventually
pushes the articulators like the tongue and alveolar bridge apart, producing a
small explosive sound (ref6). Plosive sounds in English include [p], [t], [k], [b],
[d] and [g].
Likewise, nasal consonants are similar to plosives in that they too involve
complete closure at some point along the vocal tract however the difference is
that with nasals, the velum is lowered away from the back wall of the pharynx.
Subsequently, air leaves the nose and enters the closed off oral cavity
simultaneously (ref7); in this way there is no buildup of pressure thus no
plosion as the air leaves the air leaves the nostrils. In English, these nasals
include [m], [n] and [ŋ].
Taps or flaps are produced by a single fast movement of the top of the tongue,
typically against the alveolar bridge; the [r[ sound in British accents, notably
that of Scotland is an example of this consonant.


Fricative: these are produced when air flows through a narrow channel, which
is created when two articulators (like the lower lip and upper teeth in the case
of [f]) come into contact without closure. The English fricatives include [f], [s],
[z], [v], [h], [ ʃ ] and [ʒ], [θ] and [ðð̠].
Approximants are less consonantal, and are produced when articulators
move towards closing, though not near enough produce friction or a plosive
build-up of pressure (ref9). Approximants in English include [w], [r], and [j], of
which the latter is spelt orthographically as /y/. The lateral approximant [l] is
also included in this category; it is produced when the tongue touches the
alveolar bridge, but the sides of the tongue are lowered in order to allow air to
freely leave.
Within the range of consonants between plosives and fricatives, two other
consonants are present in English, known as affricates. These tend not to be
recognised as single consonants since they are made up of two phonetic
consonants, however, they are typically treated as a single sounds. These
affricates are [ tʃ ] and [dʒ], which are found in, for example, /channel/ and
/grudge/; they are produced like plosives in that they begin with a full closure,
but instead of air building up leading to an explosive release, it is released
slowly. In this way, there is a short fricative phase, where the articulators
separate, though before they fully part (ref10).



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