quality is unknown). Old English, meanwhile, distinguished only e, a, and u (again the exact phonetic quality is unknown). Specific languages English Stress is a prominent feature of the English language, both at the level of the word (lexical stress) and at the level of the phrase or sentence (prosodic stress). Absence of stress on a syllable, or on a word in some cases, is frequently associated in English with vowel reduction – many such syllables are pronounced with a centralized vowel (schwa) or with certain other vowels that are described as being "reduced" (or sometimes with a syllabic consonant as the syllable nucleus rather than a vowel). Various phonological analyses exist for these phenomena. Latin Old Latin had initial stress, and short vowels in non-initial syllables were frequently reduced. Long vowels were usually not reduced. Vowels reduced in different ways depending on the phonological environment. For instance, in most cases, they reduced to . Before l pinguis, an not followed by , they became Old Latin and Classical Latin . Before and some consonant clusters, they became . , * > Old Latin , "make, affect" , * > , "made, affected" (participles) , * > Old Latin , "I jump, I jump on" > Latin , "I give birth, I gave birth" In Classical Latin, stress changed position and so in some cases, reduced vowels became stressed. Stress moved to the penult if it was heavy or to the antepenult otherwise. Classical Latin , , , Romance languages Vulgar Latin had seven vowels in stressed syllables (). In unstressed syllables, merged into and merged into , yielding five possible vowels. Some Romance languages, like Italian, maintain this system, while others have made adjustments to the number of vowels permitted in stressed syllables, the number of vowels permitted in unstressed syllables, or both. Some Romance languages, like Spanish, French and Romanian, lack vowel reduction altogether. Italian Standard Italian has seven stressed vowels and five unstressed vowels, as in Vulgar Latin. Some regional varieties of the language, influenced by local vernaculars, do not distinguish open and closed e and o even in stressed syllables. Neapolitan Neapolitan has seven stressed vowels and only four unstressed vowels, with e and o merging into . At the end of a word, unstressed a also merges with e and o, reducing the number of vowels permitted in this position to three. Sicilian Sicilian has