Practice with Vowels

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Practice with Vowels
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Transcription Practice
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Natural Classes

• Moving Towards Usefulness

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Description of Phonemes

• We have noticed that sounds may be described by
  listing their articulatory features. Thus, t is
  described as a voiceless alveolar stop consonant
  and a is described as a low, back, lax
  unrounded vowel.

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What is a Natural Class?

• Natural Classes are groups of sounds in a
  language that share some articulatory features.
• In order for a group to be a natural class is
  must contain all of the sounds that share a
  particular feature or group of features, and none
  that dont.

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For example

• When we refer to the natural class of voiced
  stops in English, we mean all of the sounds that
  are voiced stops in English (i.e., b, d, g),
  and no sounds that are not.

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Why Natural Class?

• Describing sounds in terms of natural classes
  makes it possible to state generalizations about
• the sound systems of human languages
• dialect variation
• changes in pronunciation in borrowed words
• the acquisition of language by children
• rules for rhyming in poetry
• processes of sound change across the history of a
  language

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So, What Is Natural?

• Consider two groups of sounds p, t, k and p,
  l, w. The first of these two groups is a natural
  class, but the second isnt.
• Why?

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Notice

• p, t, k all share the feature of voicelessness
  and they are all oral stops (as opposed to nasal
  stops m, n, N and glottal stop ?).
• In fact, these three sounds are the set of all
  sounds in English that have both the features
  voiceless and oral stop.

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But

• The set p, l, w is not a natural class because
  the only feature these three sounds have in
  common is consonant, which describes a much
  larger set of sounds.
• We might say that p, l, w is a subset of the
  natural class of consonants in English, but it is
  certainly not a natural class itself.

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Features Used to Describe Natural Classes

• All the features we have discussed so far can
  also be used to describe natural classes.
• For example, in English the vowels i, e, o, u
  are all tense vowels, and there are no other
  tense vowels in English. Thus they are members of
  the natural class of tense vowels in English.

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Wider Features

• In talking about groups of sounds, we must use a
  few features in addition to those used to
  describe individual sounds.

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Labials

• In many situations it is advantageous to refer to
  f and v together with p, b, m, w as
  belonging to the same natural class.
• For this purpose we use the feature labial.

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Sibilants

• The natural class of sibilants refers to the
  group of sounds tS, S, s, dZ, Z, z.
• Although these phonemes do not share articulatory
  features, they do share auditory features -
  namely, a high-pitched hissing sound quality.

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Obstruants and Sonorants

• Obstruants (stops, fricatives and affricates) are
  consonants produced with an obstruction to the
  airflow.
• Sonorants (nasals, liquids and glides) are
  consonants produced with a relatively open
  passage for the airflow.

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Exercises