TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: Which former Portuguese African Colony joined the British Commonwealth in 1995?

SOLUTION: commonwealth of nations

PROBLEM: Which horse won the 2008 Grand National?

SOLUTION: 2008 grand national

PROBLEM: Who had parts in 'St. Elmo's Fire', 'About Last Night ' and 'Wayne's World'?

SOLUTION:
about last night