O’zbekiston respublikasi o’rta va maxsus ta’lim vazirligi o’zbekiston davlat jahon tillari universiteti

The Formation of Speech Sounds

1. 
   Speech sounds are produced with the help of air coming from the lungs. The stream of air passes from the lungs into the windpipe. The upper part of the windpipe is called the larynx. The vocal cords are situated inside the larynx. The space or the opening between the vocal cords is called the glottis.
   
2. 
   When the vocal cords are tense and brought together, the glottis is narrowed and the stream of air passes through it with some difficulty and makes the vocal cords vibrate. The vibration of the vocal cords produces the sound of voice. Speech sounds articulated with the vocal cords in vibration are called voiced. When the vocal cords are held lose and kept apart the glottis is wide open and the stream of air passes through it freely, the vocal cords are not in vibration and no sovmd of voice is produced. Speech sounds articulated with the vocal cords loose are called voiceless.
   
3. 
   Having passed through the glottis the stream of air comes into the pharynx, where from it may pass through the mouth cavity or through the nasal cavity. This depends on the position of the soft palate.
   
4. 
   When the soft palate is raised and pressed against the back of the pharynx the passage into the nasal cavity is blocked and the stream of air passes through the mouth cavity. Speech sounds produced with the soft palate raised are called oral. When the soft palate is lowered the passage into the nasal cavity is open and the stream of air passes through the nasal cavity. Speech sounds produced with the soft palate lowered are called nasal.
   
5. 
   Entering the mouth cavity the stream of air either passes freely or encounters (meets) some kind of obstruction in the mouth cavity made by the organs of speech. Speech sounds produced with some kind of obstruction in the mouth cavity are called consonants. Speech sounds produced without any obstruction in the mouth cavity are called vowels.
   
6. 
   The obstruction may be:
   

a.complete, or b. incomplete

Complete obstruction means contact. The air passage is blocked,the stream of air either removes the obstruction producing plosion [ p,b,t,d,k,g ] or escapes some other way: either on both sides of the tongue [ b,r ] or through the nasal cavity [ m,n,ng ].

Incomplete obstruction is the narrowing of the passage through which the stream of air escapes producing friction as in [ s, z, f, v, ɜ, ʃ ].