Case marking

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Case marking is the process of assigning grammatical case values to dependent nouns for the type of relationship they bear to their heads. Usually a language is said to "have cases" only if nouns change their form (nouns decline) to reflect their case. In the UNLarium framework, case marking is defined through S-rules. Case marking is not informed in UNL.

Syntax

Case marking is defined through S-rules in the following format:

<SYNTACTIC ROLE>(+<CASE>);

Where:

  • <SYNTACTIC ROLE> is the syntactic role (VA, VC, VS, VH, etc) of the case-marked term in relation to the head; and
  • <CASE> is the grammatical case to be assigned.

Examples

VS(+NOM);
assigns the nominative case (NOM) to the specifier of the verb (VS)
VC(+ACC);
assigns the accusative case (ACC) to the complement of the verb (VC)

Observations

Conditional case-marking
Conditional case-marking may be stated by defining the left side of the s-rule and co-indexing it to the right side:
  • VC(+DAT); (unconditional case-marking: assign the dative case (DAT) to the complement of the verb);
  • VC(PP):=VC(+DAT); (conditional case-marking: assign the dative case (DAT) to the complement of the verb (VC) if it is a PP);
  • VC([make];NP):=VC(+ACC); (conditional case-marking: assign the accusative case (ACC) to the complement of the verb (VC) whose lemma is "make").
Complex case-marking
A single case-marking rule may contain several case-marking operations:
  • VS(+NOM)VC(+ACC)VA(+OBL); (assign the nominative case to the specifier of the verb, the accusative case to the complement of the verb, and the oblique case to the adjunct to the verb)
Use of "+"
As rules are conservative (i.e., features are preserved unless explicitly deleted), the use of "+" is actually optional:
  • VC(+DAT); is the same as VC(DAT);
Case-unmarking
Assigned cases may be deleted through "-":
  • VC(-ACC); (deletes the accusative case from every verb complement)
  • VC(PP):=VC(-ACC); (deletes the accusative case from verb complements which are prepositional phrases)
The symbol ^ is used for negation and to control infinite recursion
  • VC(^NOM):=VC(NOM); (assign the nominative case to the complement of verb if it does not have the nominative case)
Software