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.

Ex Input:
jena malone (born november 21, 1984, sparks, nevada) is an american actress.

Ex Output:
jena malone

Ex Input:
the family computer disk system was a disc add-on for the nintendo entertainment system that was only released in japan despite being announced in america.

Ex Output:
family computer disk system

Ex Input:
shawn colvin (born january 10, 1956 in vermillion, south dakota) is a singer-songwriter and a musician.

Ex Output:
shawn colvin