Question: Who is the person who dated Taylor Swift and has username of Harry_Styles?
Answer(s):
answer: Harry Styles

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ns:m.0dl567)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.0dl567 ns:celebrities.celebrity.sexual_relationships ?y .
?y ns:celebrities.romantic_relationship.celebrity ?x .
?x ns:internet.blogger.blog ns:m.0z1v_vj . 
}