Thematic Role System

David went to the meeting with Ashok by car.

Thematic Role
verb : go
agent : David
coagent : Ashok
destination : meeting
conveyance : car

Prepositional Constraints
Preposition, Themantic Roles
by | agent, conveyance, location
for | beneficiary, duration
from | source
to | destination
with | coagent, instrument

e.g.
That was written by Ashok.
David went to New York by train
David stood by the statue.