has part has part has_part independent continuant independent continuant material entity material entity immaterial entity immaterial 028-BFO As for fiat point, fiat line, fiat surface, site BFO 2 Reference: Immaterial entities are divided into two subgroups:boundaries and sites, which bound, or are demarcated in relation, to material entities, and which can thus change location, shape and size and as their material hosts move or change shape or size (for example: your nasal passage; the hold of a ship; the boundary of Wales (which moves with the rotation of the Earth) [38, 7, 10 ImmaterialEntity b is an immaterial entity =Def b is an independent continuant which is such that there is no time t when it has a material entity as continuant part