Nasal and laterals, for the reasons given in the previous section, are sonorants; yet they resemble the obstruents in that the oral cavity is constricted during their articulation. Obstruents, laterals and nasals from a natural class of consonantal sounds that differ phonetically from the vocalic (or non-consonantal) class of vowels and glides.
Labial : [p] [b] [m] [f] [v]
The class of labial consonants includes the class of bilabial sounds [p] [b] [m] as well as the labiodentals [f] and [v]. Bilabial and labial sounds are those articulated with the involvement of the lips.
Coronals : [t] [d] [n] [s] [z] [ʃ] [ʒ] [tʃ] [dʒ]
Coronals include the alveolars [t] [d] [n] [s] [z] the palatal [ʃ] [ʒ] and the affricates [tʃ] [dʒ]. These sounds are articulated by raising the tongue blade towards the hard palate.
Anterior
Anterior sounds are consonants produced by the front of the tongue, in in fron of the palato-alveolar area. They include bilabials, labiodentals, and alveolars.
Sibilants : [s] [z] [ʃ] [ʒ] [tʃ] [dʒ]
Another class of consonantal sounds is characterised by an acoustic rather than an articulatory property of its members. The friction created in the production of the fricatives in the words sit [sɪt] zip [zɪp], shoe [ʃu], leisure [leʒə], and measure [meʒə], and the affricates in the words church [tʃɜtʃ] and judge [dʒʌdʒ] causes a 'hissing' sound. These sounds are in a class of sibiliants.
