What's the benefit of OWL Import?

I can use qualifiers by using a namespace, why do we need to import an ontology then? For example, if I've included a lexica from WordNet in my ontology, what benefits do I have of importing the WordNet ontology in my ontology? Doe开发者_如何转开发s it help in querying using SPARQL? Any example?

By importing an ontology you gain access to its axioms, e.g. reasoning happens over the import-closure of the ontology.