 However, they are contrasted only in Greek loans; for example, native Coptic ("anzībə") and ("ansībə") 'school' are homophonous.Other consonants that sometimes appear to be either in free variation or to have different distributions across dialects are and , and (especially in the Fayyumic dialect, a feature of earlier Egyptian) and and , with the voiceless stop consonants being more common in Coptic words and the voiced ones in Greek borrowings.Apart from the liquid consonants, this pattern may indicate a sound change in Later Egyptian, leading to a neutralisation of voiced alveolar and velar plosives.