Hayu is a Kiranti language of eastern Nepal studied by Brian Houghton Hodgson in the first half of the nineteenth century. More recently, an exquisite study has been devoted to Hayu by Boyd Michailovsky. In 1990, George van Driem proposed a few alternative synchronic analyses of Hayu conjugational phenomena. Hayu verbal agreement morphology has been studied in the comparative context of Proto-Kiranti morphosyntax and Tibeto-Burman historical grammar (van Driem 1990, 1993).