Question: What city is located on the mouth of Duwamish River?
SPARQL query: SELECT DISTINCT ?uri WHERE { <http://dbpedia.org/resource/Duwamish_River> <http://dbpedia.org/ontology/riverMouth> ?x . ?x <http://dbpedia.org/property/cities> ?uri  . }
Answer: [Seattle] is located on the mouth of Duwamish River.