Generally English speech sounds are divided into two main groups, namely vowels and consonants.
Vowel Sounds A vowel is defined as a voiced sound in forming which the air issues in a continuous stream trough the pharynx and mouth, there being no obstruction and no narrowing such as would cause audible friction ( Jones, 1975: 23 ). Vowel is a sound pronounced with vibration of vocal cords but with no closure in the vocal tract above the glottis ( Ridwan, 1995 : 14 )
The qualities of a vowels depend upon the positions of the tongue and lips. It is convenient to classify them according to the position of the main part of the tongue.
English Vowels can be classified according to the following factors :
- The Position of The Tongue The position of the tongue here means the distance between the tongue and hard palate. According to these factors, vowels are classified into high vowels, mid vowels, and low vowels.
Vowel Sounds A vowel is defined as a voiced sound in forming which the air issues in a continuous stream trough the pharynx and mouth, there being no obstruction and no narrowing such as would cause audible friction ( Jones, 1975: 23 ). Vowel is a sound pronounced with vibration of vocal cords but with no closure in the vocal tract above the glottis ( Ridwan, 1995 : 14 )
The qualities of a vowels depend upon the positions of the tongue and lips. It is convenient to classify them according to the position of the main part of the tongue.
English Vowels can be classified according to the following factors :
- The Position of The Tongue The position of the tongue here means the distance between the tongue and hard palate. According to these factors, vowels are classified into high vowels, mid vowels, and low vowels.
- High Vowels are vowels produced by placing the tongue toward the hard palate, so that there is a little distance between the tongue and hard palate. The sounds are : /i: /, /i /, /u: /, /u/ .
- Mid Vowels are produced by placing the tongue between position for high vowels and low vowels. The sounds are : /e/, /έ/, /ә: /, /ә /, / / , / o /.
- Low Vowels are vowels produced by placing the tongue so low that there is a great distance between the tongue and the hard palate. The sounds are : /æ /, /٨/, /a/, /α / /
- Which Part of The Tongue is Raised ( nearest the roof of the mouth )
For practical purposes the tongue is conveniently divided into three parts :
Front Vowels, Central Vowels, and Back Vowels.
- Front Vowels are produced when the front part of the tongue is raised towards the hard palate, nearest the upper teeth ridge. The sounds are : /I : /, / l/ , /e/, and /æ /.
- Central Vowels are sounds made by raising the middle part of the
Tongue in the direction of the soft palate. The sounds are : /α/, /3 :/ and /٨/.
- Back Vowels are produced by raising the back part of the tongue in the direction of the soft palate. The sounds are : /a /, /o/, / /u/ and /u:/.
- How High in The Mouth Some Part of The Tongue Is Raised ( The degree of raising the tongue or how close is it to the roof of the mouth).
Although there may be many degrees of raising the tongue in Producing vowel sounds, ii is usually considered sufficient to distinguish only four degrees of raising. The sounds : Close Vowels, Open Vowels,
Half- Close Vowels and Half- Open Vowels.
- The Degree of Lips Rounding.
In producing vowel sound, the lips may be rounded, spread or neutral. In in describing English vowel sounds, however the use of lip position is rather superfluous, since lip position is predictable in term which part of the tongue is raised. It means that the degree of lip rounding for the back series of vowels paralleled by the degree of raising the tongue : when the tongue is highest in the mouth, the lips are extremely rounded.
According to this way, vowel sounds can be divided into two classifications. They are Rounded and Unrounded vowels.
- Rounded Vowels are vowels produced in the formation of which the lips are drown together so that the opening between them is more or less round.
The sounds are : / o / and /
- Unrounded Vowels are the vowels produced in the formation of which the lips are in the neutral position or the lips are spread out.
The sounds are : /l : /, /i / , / e /, / æ / and / a: / .