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:
Source that indicates the concrete, physical location where an event begins or a state becomes true.
Example:
Amanda drove the package FROM HOME.
Initial_Location