Example

Struture of sentence and background knowledge could help disambiguate sentences.

• There could be sentences where same word could mean differentely. here using different context we could resolve meaning
• There could be sentences where different word mean same thing. Here using same context we could resolve meaning.

Note both situations are inverse of each other.

Primitive Action

Thematic Roles and Primitive Actions

• If a concept that comes before the verb is animate, put that as agent
• If a concept that comes after the verb is inanimate, put that as object
• These are called structured knowledge representations.

Example

Note how rules and frames are working together (there is a rule on how to decide agent from sentence, for example). Also lexical, syntactic, semantic all working together here.

How do we know? Because we could ask questions. Who had the book? And all answers could come from frame.

Implied Actions

Example

Actions and Sub Actions

State Changes

We could use generic do when unable to decide what is a primitive action.

Actions and Resultant Actions

Exercise