TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: Pirate Edward Teach was better known by what nickname?

SOLUTION: edward teach

PROBLEM: Can you name the final movie directed by Alfred Hitchcock?

SOLUTION: alfred hitchcock

PROBLEM: At which city was Kai Tak airport replaced by Chek Lap Kok in 1998?

SOLUTION:
chek lap kok