#vowel_system__vowelsystem  the system of vowels used in a particular language
  supertype:  phonemic_system__phonemicsystem  the system of phonemes recognized in a language
     supertype:  language_system  a system of linguistic units or elements used in a particular language
        supertype:  system  a group of independent but interrelated elements comprising a unified whole; "a vast system of production and distribution and consumption keep the country going"
           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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