Articulatory classification of English vowels

According to Armeninan scholars vowels are subdivided into :a) monophthongs(the tongue position is stable); b) diphthongs( it changes that is the tongue moves from one position to another), c) diphthongoids ( an intermediate case: when the change in the position is fairly weak).

According to the horizontal movement phonethicians distinguish five classes: 1) front:2) front-retracted:3) central:4) back:5) back-advanced. Another feature of English vowels is lip position. Traditionally three lip positions are distinguished. Any back vowel in English is produced with rounded lips, the degree of rounding is different and depends on the height of the raised part of the tongue: the higher it is raised the more the more rounded the lips are. Character of vowel end depends on the kind of the articulatory transition from a vowel to a consonant. This transition is very closed in English unlike Armenian. As a result all English short vowels are checked when stressed. The degree of checkness may vary and depends on the following consonants (+voiceless-voiced-sonorants-). It is a common knowledge that a vowel like any sound has physical duration. When sounds are used in connected speech they cannot help being influenced by one another. Duration of a vowel depends on the following factors: 1) its own lenght:2) the accent of the syllable in which it occurs:3) phonetic context: 4) the position in a rhythmic structure: 5) the position in a tone group: 6) the position in an utterance: 7) the tempo of the whole utterance: 8) the type of pronounciation.