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.

Example Input: ignace murwanashyaka (14 may 1963 16 april 2019) was a rwandan rebel leader.
Example Output: ignace murwanashyaka

Example Input: the 193940 nhl season was the 23rd season for the national hockey league.
Example Output: 193940 nhl season

Example Input: the philadelphia inquirer is a newspaper that serves the philadelphia, pennsylvania, metropolitan area of the united states.
Example Output:
the philadelphia inquirer