is_free
Use these simple Tags to mark Instances as True or False: #is_//free #is/not_/free
Or write it as a Triple: [ is_free :: Boolean ]
A flag to signal that the item, event, or place is accessible for free.
Predicate describes that: [ #has_/domain :: PublicationEvent ] ( #has_/name :: is_free ) ( #has_/range :: Boolean )