sábado, 3 de diciembre de 2011

Consonants place and manner of articulation and vowels

Consonats

Some authorities claim one or two fewer consonants than I have shown above, regarding those with double symbols (/tʃ/ and /dʒ/) as “diphthong consonants” in Potter's phrase. The list omits one sound that is not strictly a consonant but works like one. The full IPA list of phonetic symbols includes some for non-pulmonic consonants (not made with air coming from the lungs), click and glottal sounds. In some varieties of English, especially in the south of Britain (but the sound has migrated north) we find the glottal plosive or glottal stop, shown by the symbol /ʔ/ (essentially a question mark without the dot at the tail). This sound occurs in place of /t/ for some speakers - so /botəl/ or /botl/ (bottle) become/boʔəl/ or /boʔl/.
We form consonants by controlling or impeding the egressive (outward) flow of air. We do this with the articulators - from the glottis, past the velum, the hard palate and alveolar ridgeand the tongue, to the teeth and lips. The sound results from three things:
  • voicing - causing the vocal cords to vibrate
  • where the articulation happens
  • how the articulation happens - how the airflow is controlled.
Voicing
All vowels must be voiced - they are caused by vibration in the vocal cords. But consonants may be voiced or not. Some of the consonant sounds of English come in pairs that differ in being voiced or not - in which case they are described as voiceless or unvoiced. So /b/ is voiced and /p/ is the unvoiced consonant in one pair, while voiced /g/ and voiceless /k/ form another pair.
We can explain the consonant sounds by the place where the articulation principally occurs or by the kinds of articulation that occurs there. The first scheme gives us this arrangement:

Articulation described by region
  • Glottal articulation - articulation by the glottis. We use this for one consonant in English. This is /h/ in initial position in house or hope.
  • Velar articulation - we do this with the back of the tongue against the velum. We use it for initial hard /g/ (as in golf) and for final /ŋ/ (as in gong).
  • Palatal articulation - we do this with the front of the tongue on the hard palate. We use it for /dʒ/ (as in jam) and for /ʃ/ (as in sheep or sugar).
  • Alveolar articulation - we do this with the tongue blade on the alveolar ridge. We use it for /t/ (as in teeth), /d/ (as in dodo) /z/ (as in zebra) /n/ (as in no) and /l/ (as inlight).
  • Dental articulation - we do this with the tip of the tongue on the back of the upper front teeth. We use it for /θ/ (as in think) and /ð/ (as in that). This is one form of articulation that we can observe and feel ourselves doing.
  • Labio-dental articulation - we do this with the lower lip and upper front teeth. We use it for /v/ (as in vampire).
  • Labial articulation - we do this with the lips for /b/ (as in boat) and /m/ (as in most). Where we use two lips (as in English) this is bilabial articulation.



Articulation described by manner
This scheme gives us a different arrangement into stop(or plosive) consonants, affricates, fricatives, nasal consonants, laterals and approximants.
  • Stop consonants (so-called because the airflow is stopped) or plosive consonants(because it is subsequently released, causing an outrush of air and a burst of sound) are:
    • Bilabial voiced /b/ (as in boat) and voiceless /p/ (as in post)
    • Alveolar voiced /d/ (as in dad) and voiceless /t/ (as in tap)
    • Velar voiced /g/ (as in golf) and voiceless /k/ (as in cow)
  • Affricates are a kind of stop consonant, where the expelled air causes friction rather than plosion. They are palatal /tʃ/ (as in cheat) and palatal /dʒ/ (as in jam)
  • Fricatives come from restricting, but not completely stopping, the airflow. The air passes through a narrow space and the sound arises from the friction this produces. They come in voiced and unvoiced pairs:
    • Labio-dental voiced /v/ (as in vole) and unvoiced /f/ (as in foal)
    • Dental voiced /ð/ (as in those) and unvoiced /θ/ (as in thick)
    • Alveolar voiced /z/ (as in zest) and unvoiced /s/ (as in sent)
    • Palatal voiced /ʒ/ (as in the middle of leisure) and unvoiced /ʃ/ (as at the end of trash)
  • Nasal consonants involve closing the articulators but lowering the uvula, which normally closes off the route to the nose, through which the air escapes. There are three nasal consonants in English:
    • Bilabial /m/ (as in mine)
    • Alveolar /n/ (as in nine)
    • Velar /ŋ/ (as at the end of gong)
  • Lateral consonants allow the air to escape at the sides of the tongue. In English there is only one such sound, which is alveolar /l/ (as at the start of lamp)
  • Approximants do not impede the flow of air. They are all voiced but are counted as consonants chiefly because of how they function in syllables. They are:
    • Bilabial /w/ (as in water)
    • Alveolar /r/ (as in road)
    • Palatal /j/ (as in yet)


VOWELS






English has twelve vowel sounds. In the table above they are divided into seven short and five long vowels. An alternative way of organizing them is according to where (in the mouth) they are produced. This method allows us to describe them as front, central and back. We can qualify them further by how high the tongue and lower jaw are when we make these vowel sounds, and by whether our lips are rounded or spread, and finally by whether they are short or long. This scheme shows the following arrangement:

Front vowels
  • /i:/ - cream, seen (long high front spread vowel)
  • /ɪ/ - bit, silly (short high front spread vowel)
  • /ɛ/ - bet, head (short mid front spread vowel); this may also be shown by the symbol /e/
  • /æ/ - cat, dad (short low front spread vowel); this may also be shown by /a/



Central vowels
  • /ɜ:/- burn, firm (long mid central spread vowel); this may also be shown by the symbol /ə:/.
  • /ə/ - about, clever (short mid central spread vowel); this is sometimes known asschwa, or the neutral vowel sound - it never occurs in a stressed position.
  • /ʌ/ - cut, nut (short low front spread vowel); this vowel is quite uncommon among speakers in the Midlands and further north in Britain.



Back vowels
  • /u:/ - boob, glue (long high back rounded vowel)
  • /ʊ/ - put, soot (short high back rounded vowel); also shown by /u/
  • /ɔ:/ - corn, faun (long mid back rounded vowel) also shown by /o:/
  • /ɒ/- dog, rotten (short low back rounded vowel) also shown by /o/
  • /ɑ:/ - hard, far (long low back spread vowel)
We can also arrange the vowels in a table or even depict them against a cross-section of the human mouth. Here is an example of a simple table:

FrontCentralBack
Highɪ    i:ʊ    u:
Midɛə    ɜ:ɔ:
Lowæʌɒ    ɑ:



VOWELS LINKS FOR PRACTICE
Games:

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