Question: What is the publication date  of the television series that mainly depicts slavery?
Choices:
2005-07-14
2014-06-05
2006
2005-05-24
1962-04-12
1958
2012-03-01
2003-12-11
1964-04-13
2009-04-01
Answer: 2006
SPARQL: SELECT DISTINCT ?pv WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "television series" . ?e <main_subject> ?e_1 . ?e_1 <pred:name> "slavery" .  ?e <publication_date> ?pv .  }
Program:
function: Find
inputs: slavery
function: Relate
dependencies: 0
inputs: main subject
backward
function: FilterConcept
dependencies: 1
inputs: television series
function: QueryAttr
dependencies: 2
inputs: publication date