... forests. For completeness, we assume an extended formof the transition system where transitions take theform Σ0, Σ1, B, A, p, where p is a flag takingvalues in {0, 1} which equals 0 for ... thatS is sound for a class of dependency graphs Gif, for every sentence w and transition sequence(cs(w), c1, . . . , cf) of S, g(cf) is in G, and that Sis complete for G if, for every sentence ... wk→ wi (for every k = j).Nodes in a forest that do not have a head are calledroots. Some frameworks require that dependencyforests have a unique root (i.e., are connected).Such a forest is...