#perfective_tense__perfective__perfect__perfect_tense__perfecttense  a tense of verbs used in describing action that has been completed (sometimes regarded as perfective aspect)
  subtype:  present_perfect_tense  past_perfect_tense  future_perfect_tense
  supertype:  tense  a grammatical category of verbs used to express distinctions of time
     supertype:  grammatical_category__grammaticalcategory__syntactic_category__syntacticcategory  a category of words having the same grammatical properties
        supertype:  class.aggregation__clas__family  a collection of things sharing a common attribute; "there are two classes of detergents"
           supertype:  aggregation__collection__accumulation__assemblage  several things grouped together
              supertype:  group__grouping  any number of entities (members) considered as a unit
                 supertype:  collection  something gathering separated things (entities/situations)
                    supertype:  divisible_entity__divisibleentity  many classifications under this category are application-dependant
                       supertype:  entity  something that can be "involved" in a situation
                          supertype:  thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type
                       supertype:  divisible_thing__divisiblething
                          supertype:  thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type

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