4.pronunciation : consonants: introductory note:
in uttering consonants, there is partial or complete obstruction in the mouth, with or without an obstruction in the larynx as well. the obstruction or closure in the mouth, if complete, has to be released before speech-sounds can be produced. this is usually done in such a manner that the breath is released suddenly, making an 'explosive sound'. hence the consonants thus produced are called explosives or plosives (or stops). such are, for example, the consonants b, d, g, k, p, t.
consonants uttered with a partial obstruction in the mouth so that there is friction of the outgoing breath against some part of the mouth, (resulting in a 'hissing' sound) are called friction sounds or fricatives or spirants. such are, for example, f, s, v, z. (some of these sounds have the name sibilants). consonants uttered with a partial or complete obstruction in the mouth, with an obstruction in the larynx (hence with a vibration of the vocal chords), are called voiced or soft. such are, for example, the 'plosives' b, d, g and the 'fricatives' v and z. (all the vowels are, of course, 'voiced)'. consonants uttered without an obstruction in the larynx (hence without the vibration of the vocal chords) are called voiceless or hard. such are, for example, k, p, t of the 'plosive' and f and s of the 'fricatives'. some consonants are uttered with aspiration or h-sound. these are called aspirates. such are, for example, the ckh in a word like blockhead, or the gh in a word like log-house- (ckh being an 'unvoiced aspirate' and gh being a 'voiced aspirate' when pronounced as a single sound without pause between ck and h, and g and h).
the partial or complete obstruction in the mouth can occur in any part of it, with the help of the tongue, lips and the (upper) teeth, and thus give rise to the various 'classes' of consonants. thus, for example, p and b are bi-labial stops, t and d are dental stops, s and z are alveolar fricatives, and f and v are labio-dental fricatives. in pronouncing some plosive, the breath is emitted through the nose. these are called nasals (such as n and m). in pronouncing some consonants, the tip of the tongue is 'inverted' and touches the hard plate. these are called retroflex consonants. in uttering some consonants of this (retroflex) class, the inverted tongue 'flaps' against the hard palate. these are called flapped retro flexes. the consonant r is trilled consonant. it is formed by 'a rapid succession of trill of the tongue-tip' against the ridge of the upper teeth. the consonant l is called a lateral consonant; it is formed by placing the tongue against the hard palate while the air escapes on one or both the sides. some consonants (like y and w) are called semi-vowels; they are between a consonant and a vowel, hence this name. if the closure in the mouth [see(a) above] is released slowly instead of rapidly, it results in air-friction and the plosive is combined with a fricative. consonants thus formed are called affricates. the ch in church and j in June etc. are affricates.
the first twenty-five consonants, क to म, are divided into five classes:-
क ख ग घ ङ are soft-palatals or velar (कण्ठ्य, क वर्ग, i.e. ka-class)
च छ ज झ ञ are palatals (तालव्य, ka-varga, i.e. ca-class)
ट ठ ड ढ ण are cerebrals or retroflexes (मूर्धन्य, ट वर्ग, i.e. ta-class)
त थ द ध न are dentals (दंत्य, त वर्ग, i.e. ta-class).
प फ ब भ are (bi) labials (ओष्ठ्य, प वर्ग, i.e. pa-class).
note :- is in ta-class, but it is alveolar and not dental.
these twenty-five consonants are stops.
the second letters of each class, i.e. ख, छ, ठ, थ and फ are 'aspirated' forms of the corresponding first letters क, च, ट, त and प. similarly, the fourth letters in each class घ, झ, ढ, ध and भ are aspirated forms of the corresponding third letters, ग, ज, ड, द and ब; they are pronounced with an h-sound. the first and the second letters of each class are 'voiceless', the remaining three are 'voiced'. the fifth letters of each class, ङ, ञ, ण, न and म are nasals. in this and the following sections, the inherent अ in क etc. has been ignored.