Question: Name the three major rivers located in South America.?
Answer(s):
answer: Rio Negro
answer: Orinoco
answer: Amazon River

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ?c)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
?c ns:common.topic.image ns:m.02gqrbz . 
?c ns:location.location.contains ?x .
?x ns:common.topic.notable_types ns:m.01xs05k .
?x ns:geography.river.discharge ?sk0 .
}
ORDER BY DESC(xsd:float(?sk0))
LIMIT 3