what is the {start time} for {Cantabria} has {head of government} as {Miguel Ángel Revilla} ?
When did Miguel Angel Revilla become the President of Cantabria?
In what year did Miguel Ángel Revilla become President of Cantabria?
SELECT ?i WHERE { ?a property:start_time ?i . resource:Cantabria property:head_of_government ?a . ?a property:head_of_government resource:Miguel_Ángel_Revilla }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q3946> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P6> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q2733616> .
?statement <http://www.wikidata.org/entity/P580> ?value. 
} 

SELECT ?value WHERE { wd:Q3946 p:P6 ?s . ?s ps:P6 wd:Q2733616 . ?s pq:P580 ?value}