 Trigger type/ Event type : the type of an event;  Argument: the entity mentions involved in an event;  Argument role : the relation of an argument to an event where it part icipates.
the event extraction task is div ided into four co mponents:  Trigger identification: to distinguish true trigger mentions from pseudo trigger mentions;  Event type determinati on: to classify trigger mentions by event types;  Argument i dentification: to distinguish true arguments from pseudo arguments;  Argument role determinati on: to classify arguments by argument roles.