Question: Which airport is the hub of Delta Air Lines?
Paraphrase: Delta Airlines has it's hub located in what major airport?
SPARQL (Wikidata):  select distinct ?obj where { wd:Q188920 wdt:P113 ?obj . ?obj wdt:P31 wd:Q1248784 } 
Answer: Hartsfield–Jackson Atlanta International Airport, LaGuardia Airport, Salt Lake City International Airport, Detroit Metropolitan Wayne County Airport, Logan International Airport, Memphis International Airport, Los Angeles International Airport, Amsterdam Airport Schiphol, Seattle–Tacoma International Airport, Narita International Airport