Question: What airport has an airline hub for American Airlines?
Paraphrase: What airplane terminal has an carrier center for American Airlines?
SPARQL (Wikidata):  select distinct ?obj where { wd:Q32396 wdt:P113 ?obj . ?obj wdt:P31 wd:Q1248784 } 
Answer: O'Hare International Airport, LaGuardia Airport, Dallas/Fort Worth International Airport, Philadelphia International Airport, Charlotte/Douglas International Airport, Ronald Reagan Washington National Airport, Phoenix Sky Harbor International Airport, Los Angeles International Airport