Question: Which Maryland county borders Prince William County?
Choices: Baltimore County
Carroll County
Montgomery County
Frederick County
Allegany County
Harford County
Kent County
Charles County
Fauquier County
Loudoun County
SPARQL: SELECT DISTINCT ?e WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "county of Maryland" . ?e <shares_border_with> ?e_1 . ?e_1 <pred:name> "Prince William County" .   }
Program:
function: Find
inputs: Prince William County
function: Relate
dependencies: 0
inputs: shares border with
backward
function: FilterConcept
dependencies: 1
inputs: county of Maryland
function: What
dependencies: 2
Answer: Charles County