Orel's paradigm for periods of Proto-Albanian, and presents the relationship between the synchronic phonologies of both "EPA" and "LPA" with diachronic relationships to each other and to ancestral Indo-European forms as well as descendant Albanian forms. Stress In Early Proto-Albanian, stress was paradigmatic, and behaved according to morphological class, with a base on the first syllable. In different paradigms, the stress pattern was varyingly barytonic, oxytonic, and mobile. Unstressed vowels lost one mora—long vowels were shortened, already short vowels were often deleted. In Later Proto-Albanian, however, a new system of unstressed vowel reduction emerged where *a reduced to *ë while all others were simply deleted (except for post-tonic inlaut vowels, which became *ë). Orel gives the following examples: EPA * "ram" (sg) > *dauš > ... > modern dash EPA * "rams" (pl) > *dauši > ... > modern desh EPA * "branch" (sg) > *déga > ... > modern degë EPA * "branches" (pl) > *dégai > ... > modern degë Vowels Early Proto-Albanian possessed four distinctive short vowels: *a, *e, *i and *u. Proto-Indo-European *o and *ə had merged into *a by the Early Proto-Albanian stage. A five-way distinction was maintained for long vowels: *aː, *eː, *iː, *oː and *uː. Early Proto-Albanian also had four diphthongs: *ei, *ai, *eu and *au. Early Proto-Albanian's vowel inventory began to change as a result of Latin contact. Initially Albanian was resistant to the restoration of short *o as a separate phoneme, with Latin unstressed *o being replaced by *a, and stressed Latin *o being replaced by *u. However, in later loans, Latin *o is maintained in Albanian as *o. Additionally, some Latin loans with short *u saw Latin *u replaced by *o, as well as *ə specifically in unstressed positions before sonorants. In two cases, Orel argues that Latin short /u/ was lengthened in Albanian to /u:/, ultimately to render /y/. On the other hand, whatever effect Ancient Greek loanwords had at their time of absorption is unclear, but diachronically the vowels always agree with regular internal Albanian developments. Late Proto-Albanian Late Proto-Albanian exhibited *a, *i and *u throughout its development as distinctive short vowels. *o was restored to the phonemic inventory as a result of loanwords where it was increasingly maintained instead of replaced. Although *e was eliminated by breaking to *ie (which would render je and ja), it was restored by the leveling of /ai/ to /e/ and other