“…Several researchers working in South America (Briggs, 1993;Fock, 1963;Graham, 1993Graham, , 1995Riviere, 1971;Urban, 1986Urban, , 1988Urban, , 1991, for example, have described ceremonial encounters, public displays of mourning, and other social events where the speech of several people overlaps in complex and yet partly predictable ways. In some cases, the individuals involved echo each other's speech, in other cases, they contribute in distinct ways, for instance, by providing short responses, which might indicate approval or understanding.…”