mapped to the SUBJ (subject) relation. If there is no [-o] argument then the first [-r] argument is mapped to the SUBJ relation. If neither of these apply, then you add the plus value ([+r] or [+o]) to the feature structure and apply the following mappings: [-o,-r]: SUBJ, [+o, -r]: Object (OBJ), [-o,+r]: prepositional marked oblique (OBLθ), [+o, +r]: prepositionally marked object (OBJθ). These mappings are further constrained by the following constraints: Function argument biuniqueness: Each a-structure role corresponds to a unique f-structure function, and each f-structure function corresponds to a unique a-structure role The Subject Condition: Every verb must have a SUBJ F-structures are further constrained by the following two constraints which do much of the same labor as the θ-criterion: Coherence requires that every participant in the f-structure of a sentence must be mentioned in a-structure (or in a constituting equation) of a predicate in its clause. Completeness: An f-structure for a sentence must contain values for all the grammatical functions mentioned in a-structure. Head-driven phrase structure grammar (HPSG) Head-driven phrase structure grammar (HPSG) (for a textbook introduction, see ) does not use theta roles per se, but divides their property into two distinct feature structures. The number and category are indicated by a feature called ARG-STR. This feature is an ordered list of categories that must cooccur with a particular verb or predicate. For example, the ARG-STR list of the verb give is <NP, NP, PP>. The semantic part of theta roles (i.e. the thematic relations) are treated in a special set of semantic restriction (RESTR) features. These typically express the semantic properties more directly than thematic relations. For example, the semantic relations associated with the arguments of the verb give are not agent, theme and goal, but giver, given, givee. Approaches that eschew theta roles Many approaches to grammar including construction grammar and the Simpler Syntax model (see also Jackendoff's earlier work on argument structure and semantics, including and ) claim that theta roles (and thematic relations) are neither a good way to represent the syntactic argument structure of predicates nor of the semantic properties that they reveal. They argue for more complex and articulated semantic structures (often called Lexical-conceptual structures) which map onto the syntactic structure. Similarly, most typological approaches to grammar, functionalist theories (such as functional grammar and Role and Reference Grammar , and dependency grammar do not use theta roles, but they may