156 Morocomarca today although it occurs in the nearby dia- lect of Jopoqueri. 4-3.21.3 Stop-voicing rules Stop phonemes are usually voiceless in Aymara. Voicing, if any, is subphonemic. It may be accompanied by frication, the stop in question changing to a homor- ganic voiced fricative. 4-3.21.31 Voicing and frication of intervocalic plain stops This occurs optionally in all Aymara dialects in the demonstratives aka 'this' and uka ‘that' when they occur suffixed. It occurs occasionally in certain other morphemes, in some dialects. It occurs before but not after a stressed vowel and most often in fast speech. Examples: aka [a4ka] ‘this' (never *[a4ga]) (all dialects) uka [dka] ‘that' (never *[dga]) (all dialects) Kuna.rak aka.sti? [agdsti] ‘What is this?' (Huancané) uka.t [ugdt] 'then' uka.x [ugéx] '‘that' (all dialects) uka.t.raji [ugatraji] ‘and then’ (Calacala) An example from Calacala with uka.n ‘in there, in that place' shows diphthong avoidance as well as