Question: What are the things whose leader was a monarch Willem-Alexander of the Netherlands?
SPARQL query: SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/ontology/monarch> <http://dbpedia.org/resource/Willem-Alexander_of_the_Netherlands> . ?uri <http://dbpedia.org/ontology/leader> ?x  . }
Answer: The legislatures whose leader's monarch is Willem-Alexander of the Netherlands are [States of Groningen, Sint Maarten, Curaçao, Aruba, Netherlands, People's Party for Freedom and Democracy, Ministry of General Affairs (Netherlands), Kingdom of the Netherlands, States of North Holland, Aruban People's Party, Democratic Party Sint Maarten, National Alliance (Sint Maarten)].