what is the {appointed by} for {John Dryden} has {position held} as {Poet Laureate of the United Kingdom} ?
What Poet Laureate of the United Kingdom was positioned by John Dryden?
Appointed by John Dryden, who held the position as Poet Laureate of the United Kingdom?
SELECT ?b WHERE { resource:John_Dryden property:position_held ?m . ?m property:appointed_by ?b . ?m property:position_held resource:Poet_Laureate_of_the_United_Kingdom }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q213355> .
?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> <http://wikidata.dbpedia.org/resource/Q877838> .
?statement <http://www.wikidata.org/entity/P748> ?value. 
} 

SELECT ?value WHERE { wd:Q213355 p:P39 ?s . ?s ps:P39 wd:Q877838 . ?s pq:P748 ?value}