:my-concept a skos:Concept ; skos:prefLabel "Knowledge"@en . has preferred label This is used to specify the label of a subject (modelled as an instance of `skos:Concept`) or a subject scheme (`skos:ConceptScheme`). A resource has no more than one value of `skos:prefLabel` per language tag, and no more than one value of `skos:prefLabel` without language tag. The preferred lexical label for a resource, in a given language.