Gábor Recski will talk about an ongoing project on parsing various semantic graph structures. The Alto library implements IRTGs, which maps CFG rules to operations in any algebra. Alto comes with many algebra implementations, one of them is s-graph grammar, functionally equivalent to Hyperedge Replacement Grammars. Alto and s-grammars have previously been used for semantic parsing. We shall explore how they can be used to parse both dependency graphs and 4lang graphs, how one can be transformed into another, and how both 4lang-style definitions and basic 4lang operations such as expansion can be performed, all within the scope of s-graph grammars.