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.

[Q]: canada day is a national and an official holiday in canada celebrating its anniversary of confederation.
[A]: canada day


[Q]: danilo alvim (3 december 1920 – 16 may 1996) is a former brazilian football player.
[A]: danilo alvim


[Q]: the polo grounds was a sports stadium in new york city.
[A]:
polo grounds