what is the {object has role} for {Mary Poppins} has {film crew member} as {Hal Ambro} ?
What role did Hal Ambro play in the film crew of Mary Poppins?
What was film crew member Hal Ambro's roll for Mary Poppins?
SELECT ?p WHERE { ?b property:film_crew_member resource:Hal_Ambro . ?b property:object_has_role ?p . resource:Mary_Poppins property:film_crew_member ?b }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q209170> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P3092> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q3125876> .
?statement <http://www.wikidata.org/entity/P3831> ?value. 
} 

SELECT ?value WHERE { wd:Q209170 p:P3092 ?s . ?s ps:P3092 wd:Q3125876 . ?s pq:P3831 ?value}