Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.

Input: Consider Input: a private prison is a prison run by a private company instead of the government.

Output: private prison


Input: Consider Input: parnassiinae is a subfamily of butterflies.

Output: parnassiinae


Input: Consider Input: cuba gooding, jr. (born january 2, 1968) is an american actor.


Output: cuba gooding, jr.