What is the {position} for {office held by head of state} of {Roman Empire}
In the Roman Empire, what is the name of the highest position?
What was the position held by the head of stage in the Roman Empire?
SELECT DISTINCT ?t WHERE { resource:Roman_Empire property:office_held_by_head_of_state ?t . ?t rdf:type ontology:position }
select distinct ?obj where { ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q2277> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P1906> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj . ?obj <http://www.wikidata.org/entity/P31> <http://wikidata.dbpedia.org/resource/Q4164871> } 
 select distinct ?obj where { wd:Q2277 wdt:P1906 ?obj . ?obj wdt:P31 wd:Q4164871 } 
Roman emperor