Definition:
Actor in an event who initiates and carries out the event intentionally or consciously, and who exists independently of the event.
Example:
THEY decided to go.
Agent
Definition:
Undergoer that is central to an event or state that does not have control over the way the event occurs, is not structurally changed by the event, and/or is characterized as being in a certain position or condition throughout the state.
Example:
THE BALL rolled down the hill.
Theme
Definition:
Way or style of performing an action, or the degree/strength of a cognitive or emotional state.
Example:
We lived ON $10 PER DAY.
Manner