Agent and theme
Instrument and experiencer
The entity that preforms the action •
technically known as the agent and the
entity that is involved in or affected by
the action is called the theme (or
sometimes the ‘patient’)
•
•
•
•
•
The boy kicked the ball.
The wind blew the ball away.
A car ran over the ball.
The dog caught the ball.
•
•
If an agent uses another entity in
order to perform an action, that
other entity fills the role of
instrument.
When a noun phrase is used to
designate an entity as the person
who has a feeling, perception or
state, it fills the semantic role of
experiencer.
In the sentences The boy cut the
rope with an old razor and He drew
the picture with a crayon, the noun
phrases an old razor and a crayon
are being used in the semantic role
of instrument.
If we see, know or enjoy
something,
we’re
not
really
performing an action (hence we are
not agents).
Location, source and goal
A number of other semantic roles
designate where an entity is in the
description of an event. Where an
entity is (on the table, in the room)
fills the role of location. Where the
entity moves from is the source (from
Chicago) and where it moves to is the
goal (to New Orleans), as in We drove
from Chicago to New Orleans.