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:
the bighorn sheep ("ovis canadensis") is a species of sheep.

Ex Output:
bighorn sheep


Ex Input:
county monaghan (in gaelic ) is a county in ireland.

Ex Output:
county monaghan


Ex Input:
viriato clemente da cruz, an angolan poet and politician, was born in 1928 in kikuvo (porto amboim), angola and died in beijing, china on 13 june 1973.

Ex Output:

viriato clemente da cruz