Core Arguments

Core arguments are syntactically required by the verb; their omission renders a clause ungrammatical or radically alters its meaning. This distinguishes them from adjuncts, which provide optional circumstantial information.

• Test: The did so pro-form test replaces the verb phrase but retains core arguments
• Example: In 'She placed the book on the shelf,' removing the book yields an ungrammatical clause
• Contrast: 'She read the book [in the garden]' — the bracketed adjunct can be freely omitted
• Valency: Verbs like give are trivalent, requiring three core arguments (Agent, Theme, Recipient)

Core arguments may be syntactically unrealized yet semantically present. These null arguments are licensed by specific syntactic environments and language-specific parameters.

• Pro-drop: Languages like Spanish and Italian allow subject pronouns to be omitted ('pro hablo español')
• Object drop: 'John ate ∅' — the food argument is implicit but recoverable from context
• Passive demotion: 'The window was broken ∅' — the Agent is syntactically suppressed
• Control constructions: 'Mary promised PRO to leave' — the unpronounced subject of leave is controlled by Mary
• Imperatives: 'Close ∅ the door!' — the addressee Agent is implicit

Predicates impose semantic type constraints on their arguments, restricting the ontological category of entities that can logically fill a role. These preferences are graded, not absolute.

• Violation detection: 'The rock ate the sandwich' — rock violates the animacy preference of eat
• Metonymy resolution: 'The White House issued a statement' — the location stands for the institution
• Coercion: 'She began the book' — book is coerced into an event reading (reading/writing)
• Modeling: Selectional preferences are learned from distributional statistics over large corpora
• Application: Used in SRL to prune impossible argument candidates and improve classification accuracy

Core arguments are licensed by the predicate's lexical entry, while adjuncts are freely attachable modifiers that add circumstantial detail without being subcategorized for.

• Licensing: Arguments are specified in the verb's lexical entry; adjuncts are not
• Iterability: Adjuncts can be stacked ('She sang [in the park] [on Tuesday] [with a microphone]')
• Mobility: Adjuncts move more freely in the clause than arguments
• VP-ellipsis: 'She read the book in the garden, and he did so in the kitchen' — adjuncts survive ellipsis
• Semantic scope: Arguments complete the predicate; adjuncts modify the entire event

These verbs require only a single core argument, typically the entity undergoing the action or state.

• Unergative verbs: The subject is an active, volitional Agent.
  • Example: "The engine roared." (Agent)
• Unaccusative verbs: The subject is a Patient or Theme that undergoes a change of state or location.
  • Example: "The window shattered." (Patient)
  • Example: "The package arrived." (Theme)

These verbs require two core arguments: a subject and a direct object. The semantic roles map to the Agent-Patient prototype.

• Agent + Patient: The subject acts upon the object.
  • Example: "The technician calibrated the sensor." (Agent calibrates Patient)
• Agent + Theme: The subject moves or creates the object.
  • Example: "The compiler generated the bytecode." (Agent generates Theme)
• Experiencer + Stimulus: The subject perceives or feels the object.
  • Example: "The model detected an anomaly." (Experiencer detects Stimulus)

These verbs require three core arguments, typically involving transfer of possession or communication. The structure maps to Agent, Theme, and Recipient.

• Dative Alternation: The Recipient can appear as an indirect object or a prepositional phrase.
  • Example: "The admin assigned the user a new token." (Agent assigns Recipient Theme)
  • Alternation: "The admin assigned a new token to the user." (Agent assigns Theme to Recipient)
• Benefactive Construction: An action is performed for someone's benefit.
  • Example: "The script provisioned the developer a test environment." (Agent provisioned Beneficiary Theme)

A verb class where the transitive form (causative) and intransitive form (inchoative) share the same lexical root. The object of the transitive verb becomes the subject of the intransitive verb.

• Transitive (Causative): An Agent causes a change of state in a Patient.
  • Example: "The heat melted the solder." (Agent melts Patient)
• Intransitive (Inchoative): The Patient undergoes the change of state spontaneously.
  • Example: "The solder melted." (Patient melted)
• Other examples: break, open, freeze, reboot, sync.

These verbs require a prepositional phrase as a core argument, not an optional adjunct. The preposition is specified by the verb's semantic frame.

• Locative Prepositions: The argument specifies a location or path.
  • Example: "The pointer points to the memory address." (Theme points to Goal)
• Oblique Arguments: The preposition is lexically determined by the verb.
  • Example: "The outcome depends on the initial seed." (Theme depends on Stimulus)
  • Example: "The engineer referred to the specification." (Agent referred to Theme)

These verbs take a full clause (finite or non-finite) as a core argument, typically the Theme or Proposition.

• Finite Clause (that-clause): The argument is a tensed proposition.
  • Example: "The log indicated [that the connection timed out]." (Stimulus indicates Proposition)
• Non-finite Clause (to-infinitive): The argument is an untensed action.
  • Example: "The scheduler attempted [to allocate more memory]." (Agent attempts Action)
• Interrogative Clause (wh-clause): The argument is an embedded question.
  • Example: "The query determines [whether the index exists]." (Agent determines Question)