What is {position held} of {DeWitt Clinton} that is {end time} is {1807-1-1} ?
What position did DeWitt Clinton hold in 1807?
What was DeWitt Clinton's position on 1-1-1807?
SELECT ?v WHERE { resource:DeWitt_Clinton property:position_held ?k . FILTER ( CONTAINS ( YEAR ( ?e ) , '1807' ) ) . ?k property:position_held ?v . ?k property:end_time ?e }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q527462> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P39> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P582> <1807-1-1>
} 

SELECT ?obj WHERE { wd:Q527462 p:P39 ?s . ?s ps:P39 ?obj . ?s pq:P582 ?x filter(contains(YEAR(?x),'1807')) }