Primitive Adûnaic only had three vowels [a], [i] and [u], which could be short or long (SD/422). In early loan words from Primitive Elvish, the Elvish vowels [e,o] generally became ✶Ad. [i,u], but sometimes short Elvish [ĕ,ŏ] became ✶Ad. [ă], especially in unstressed syllables before [r] or where [a] was otherwise favored in Adûnaic (SD/423).