what is the {start time} for {John McEnroe} has {spouse} as {Patty Smyth} ?
John McEnroe married Patty Smyth in what year?
In what year did John McEnroe marry Patty Smyth?
SELECT ?k WHERE { resource:John_McEnroe property:spouse ?g . ?g property:spouse resource:Patty_Smyth . ?g property:start_time ?k }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q16474> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P26> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q444096> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q16474 p:P26 ?s . ?s ps:P26 wd:Q444096 . ?s pq:P580 ?value}