COMMENT: A widely spread common NC root. In PL and PAand. the root has a class prefix *w- (in PAand. it has replaced the original r-: we would expect in PA *rišo- as a regular reflex of the structure *HRVCV̆); we should stress that in PD and Lak. initial d- and t:- are not class prefixes, but regular protheses in this phonetic structure.
