SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/ontology/riverMouth> <http://dbpedia.org/resource/Lake_Washington> . ?x <http://dbpedia.org/property/sourceLocation> ?uri . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/River>}
Where does the rivers ending in lake washington begin?
SELECT DISTINCT ?l WHERE { ?q property:river_mouth resource:Lake_Washington . ?q property:source_location ?l . ?q rdf:type ontology:River }
Seattle, Mountlake Terrace, Washington
The source location of the river whose river mouth is Lake Washington are [Seattle, Mountlake Terrace, Washington].
The source of the river, whose mouth flows into Lake Washington, is [Seattle, Mountlake Terrace, Washington].