Question: How is Burlington whose official opening date is 1947 related to Amtrak?
Choices:
costume designer
material used
programming language
league
military casualty classification
professorship
operator
executive producer
operating system
derivative work
Answer: operator
SPARQL: SELECT DISTINCT ?p WHERE { ?e_1 <pred:name> "Burlington" . ?e_1 <date_of_official_opening> ?pv . ?pv <pred:year> 1947 . ?e_2 <pred:name> "Amtrak" . ?e_1 ?p ?e_2 .  }
Program:
function: Find
inputs: Burlington
function: FilterYear
dependencies: 0
inputs: date of official opening
1947
=
function: Find
inputs: Amtrak
function: QueryRelation
dependencies: 1
2