Did {Elton_John} {instrument} {piano}?
Is Elton John a piano player?
Does Elton John play the piano?
ASK WHERE { resource:Elton_John property:instrument resource:piano }
 ASK { ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q2808> . ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P1303> . ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q5994>. } 
ASK WHERE { wd:Q2808 wdt:P1303 wd:Q5994 }