11. It is one of two reduced vowels that are collectively known as the yers in Slavic philology. 12. In fact, it is not clear that a reduced vowel should be considered as comprising a whole syllable. 13. In polysyllabic words, the front-back distinction is lost in reduced vowels : all become mid-central. 14. The phonetic value of such reduced vowels differs depending both on the value of original vowel and the dialect spoken. 15. Long vowels were systematically marked by a dot below the letter, while the reduced vowel schwa was marked by ? 16. With vowels represented as and, it may be hard to ascertain whether they represent a full vowel or a reduced vowel . 17. The Obdorsk dialect has retained full close vowels and has a nine-vowel system : full vowels and reduced vowels ). 18. When assuming a separate set of reduced vowels , the former may end with, while the latter may end with an unreduced. 19. That is, the jaw, which to a large extent controls vowel height, tends to be relaxed when pronouncing reduced vowels . 20. The vowel itself does not exist as a phoneme in other Slavic languages, though a similar reduced vowel transcribed as does occur.