Theoretical Grammar The subject-matter of theoretical grammar. Its relation to practical grammar

Articulatory and physiological classification of English consonants. Accord to the manner of noise production and the type of obstruction, position of the soft palate.
Трахтеров, Торсуев, Васильев and other phoneticians consider the principal of consonant classification according to the manner of noise production and the type of obstruction to be one of the most important.
First of all they suggest a classification according to the manner of noise production from the viewpoint of the closure (преграда). Complete (смычные) closure then occlusive (взрывные) [p,b,t,d,k,g] and nasal consonants [m,n, h]are produced, incomplete (щелевые) closure, then constrictive (фрикативные) consonants are produced:[f,v,ɵ,ð], [ф,в,с,з], the combination of the 2 closures, then affricates are produced [t∫, dЗ] [ц, ч], intermittent (прерывистый) closure then rolled (дрожащие) consonants are produced. Rus [р,р’]
a) according to the principal of voice or noise prevalence, rus. phoneticians suggest a subdivision of the group of occlusives (взрывные) and the group of constrictives (фрикативные) into noise sounds and sonorants. Noise occlusive sonorants are called nasals.
The group of the occlusive-constrictive consonants consists of noise sounds [t∫, dЗ] rus [ч,ц].
b) Rus phoneticians subdivide the rolled, oclussive, constrictive or clussive-constrictive consonants into unicentral and bicentral, according to the number of noise producing or foci.
c) According to the shape of the narrowing constrictive cons and affricates are subdivided into sounds with flat narrowing and round narrowing. The cons / f,v,ð,Ө,∫/ are pronounced with the flat narrowing; the cons / s,z, w, ц/ are pronounced with the round narrowing.
According to the position of the soft palate all cons are subdivided into oral and nasal. When the soft palate is raised and the air into the mouth cavity oral cons are produced /p,t.k,f,v/. When the soft palate is lowered and the air on its way out passes through the nasal cavity, nasal cons are produced /m,n ŋ/.

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