query: #Rivers Taiwan
  SELECT ?river ?riverLabel ?location
  WHERE
  {
    ?river wdt:P31/wdt:P279* wd:Q355304; 
           wdt:P17 wd:Q865.
    OPTIONAL { ?river wdt:P625 ?location. }
    SERVICE wikibase:label { bd:serviceParam wikibase:language "zh". }
  }