Question: Which country with the top level domain of at has German as its official language?
Answer(s):
answer: Austria

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ns:m.04306rv)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.04306rv ns:language.human_language.countries_spoken_in ?x .
?x ns:location.country.official_language ns:m.04306rv .
?x ns:location.country.internet_tld ns:m.03y0xd . 
}