Case roles, according to the work by Charles J. Fillmore (1967), are the semantic roles of noun phrases (NP) in relation to the syntactic structures that contain these noun phrases. The term case role is most widely used for purely semantic relations, including theta roles and thematic roles, that can be independent of the morpho-syntax. The concept of case roles is related to the larger notion of Case (with a capitalised C), which is defined as a system of marking dependent nouns for the type of semantic or syntactic relationship they bear to their heads. Case traditionally refers to inflectional marking.
The relationships between nouns and their containing structures are of both syntactic and semantic value. The syntactic positional relationships between forms in sentences vary cross-linguistically and allows grammarians to observe semantic values in these nouns by examining their syntactic values. Using these semantic values gives the base for considering case roles in a specific language. In addition to its relation to Case (case based on syntactic structures), these semantic notions of case role are also closely related to morphological case.
{| class="wikitable"
|-
! Case Role !! Description !! Example
|-
| Patient || Fillmore refers to this case role as 'object' or 'objective' and can be described in three ways:
- an entity viewed as existing in a state or undergoing change
- an entity viewed as located or moving
- an entity viewed as affected by an entity
||
<br />1. The sky is blue.<br />2. The lion is in the cave.<br />3. The bird ate the worm.
|-
| Agent || An entity that performs an activity or brings about a change of state || The robots assembled the car.
|-
| Instrument || The means by which an activity or change of state is carried out || She squashed the spider with a slipper.
|-
| Experiencer || The creature experiencing an emotion or perception || They love music.
|-
| Location || The position of an entity, referring to both the temporal and spatial roles
||
The vase is on the table. <br />or <br />Canada Day is on a Tuesday.
|-
| Source || The point from which an entity moves or derives || They got news from home.
|-
| Destination || The point to or towards which an entity moves or is oriented || He turned to the altar and walked towards it.
|-
| Recipient || A sentient destination || She gave her spare change to the collectors.
|-
| Purpose || The purpose of an activity || He went to the Red Rooster for some take-out.
|-
| Beneficiary || The animate entity on whose behalf an activity is carried out || She did the shopping for her mother.
|-
| Manner || The way in which an activity is done or the way in which a change of state takes place || He did it with great skill.
|-
| Extent || The distance, area or time over which an activity is carried out or over which a state holds || It lasted the winter.
|-
| Possessor || The entity that possesses another entity || I saw John's golf clubs.
|}
Early contributions to case role
Roman Jakobson's work on case roles in Russian
In his article on the case system of Russian, Roman Jakobson (1958) closely examines case assignment and argues for a feature decomposition of case on the basis of semantic considerations. Jakobson (1958) proposed a three-feature binary case system for Russian case which includes the following: ±marginal, ±quantifying, and ±ascriptive, where the negative value is considered to be unmarked. The term marginal distinguishes the direct and non-direct cases; only the -marginal cases may occur in subject and object position. Quantifying indicates the relevance of the extent to which the noun is a participant in the event. Ascriptive puts emphasis on directionality. The reasons for having more than one case role is due to the differences in the sentences’ semantic effects.
Examples in Kannada
Kannada (a language spoken in India with overt usage of case in its suffixes) affords some good evidence of how multiple case roles can be assigned to NPs in the following two examples: (1) how NPs can be assigned either Object or Location case roles, and (2) how NPs can be assigned either Agent or Experiencer case roles. Morphological case is typical of complements and is licensed by structural Case. By contrast, semantic case is typical of adjuncts; it is only licensed by the meaning of the head. on the "case-semantics" in case-languages demonstrating how morphological case is not blind to semantics:
- Agentive subjects are nominative
- Indirect objects are either dative or accusative
- Most benefactive (indirect or direct) objects are dative
- Most malefactive (indirect or direct) objects are accusative
- Instrumental DP-objects are dative
- If a lexical item has a choice between an accusative or a dative complement, then that choice is normally semantically controlled
Morphological vs. structural
Morphological case is related to structural Case (based on syntax) in the following ways:
Structural Case is a condition for arguments that originates from a relational head (e.g. verb), while morphological case is a property that depends on the NP or DP complement. The accusative case is assigned through a structural relation between the verbal head and its complement.
Eight commonly seen cases (Indo-European case):
{| class="wikitable"
|-
! Case !! Characteristics
|-
| Nominative ||
- Indicates the subject, as the specifier of a finite verb
- Recent research indicates nominative is distinct from ergative case This distinction is characterized by the type of clauses a language allows, such as ergative, absolutive, accusative, and nominative. The distinction made between language type and clause type is illustrated in the table below: Case theory includes an inventory of structural Case and a series of lexical cases that are assigned (in all languages) at the level of the deep structure in conjunction with theta role assignment.
{| class="wikitable"
|-
! Case !! Singular form !! Plural form
|-
| Nominative
:nominativus
|| somnus
|| somni
|-
| Accusative
:accusativus
||somnum
||somnos
|-
| Genitive
:genitivus
||somni
||somnorum
|-
| Dative
:dativus
||somno
||somnis
|-
| Ablative
:ablativus
||somno
||somnis
|-
| Locative
:locativus
||somni
||somnis
|-
| Vocative
:vocativus
||somne
||somni
|}
Modern German
In modern German, all noun phrases show case forms with case generally being marked on the determiner. However, for the genitive form German marks the noun with a morphologically overt case form (this case form is retained on noun phrases in modern English, surfacing as -'s).
This hierarchy is to be interpreted as follows: If a language has a case that is listed on the hierarchy, it will usually have at least one case from each position to the left. If a language has a dative case, it will have a genitive (position to the left), an accusative or ergative case or both, and a nominative. There are times when none of the cases in one system will correspond with any of the cases in the other system. For example, the dative in Ancient Greek does not correspond closely with the dative of Latin. So when comparing cases across languages, the functions of a particular case need to be considered, rather than the labels the language has assigned. For example the distribution of accusative case:
:Accusative case assignment: