Note that the aforementioned six relation types are chosen by (1) discarding During, During Inv, and Identity, and (2) combining the two relation types in each of the five pairs, namely (Before, After), (IBefore, IAfter), (Includes, Is Included), (Begins, Begun By), and (Ends, Ended By), into a single type because they are inverses of each other.
if a relation instance (e 1 , e 2 ) is anno-  Table 1: The 14 temporal relations and their frequency of occurrences in TimeBank (v1.2).