if something contains something else then that something else can be found in that something
naturally_occurring_tangible_substance is tangible_thing. else is river. separated_thing is not divided_thing. find_inside is not things. naturally_occurring_tangible_substance is not tangible_thing. else is not river. space is what_between_else. storage is not somewhere_to_put_things. space is not what_between_else. thing is substance.