Question: When  did Lionel Messi participate in the Summer Olympic Games?
Choices:
1987-09-28
1981-04-10
1987-11-18
1992-04-18
1918-02-16
2008-08-08
1941-09-19
1861-05-07
1999-01-12
1956-06-29
Program:
function: Find
inputs: Lionel Messi
function: Relate
dependencies: 0
inputs: participant of
forward
function: FilterConcept
dependencies: 1
inputs: Summer Olympic Games
function: QueryAttr
dependencies: 2
inputs: start time
SPARQL: SELECT DISTINCT ?pv WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "Summer Olympic Games" . ?e_1 <participant_of> ?e . ?e_1 <pred:name> "Lionel Messi" .  ?e <start_time> ?pv .  }
Answer: 2008-08-08