Question: Which of the volcanoes that erupted in 1550 is still active?
SPARQL:
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX res: <http://dbpedia.org/resource/>
SELECT DISTINCT ?uri 
WHERE {
        ?uri rdf:type dbo:Volcano . 
        ?uri dbo:eruptionYear ?y .
        FILTER (year(?y) = 1550)
        ?uri text:"is" text:"active" . 
}