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:
jeong mong-ju (, hanja:鄭夢周, 1337 - april 1392) was a korean goryo dynasty politician, writer, poet and thinker.

Ex Output:
jeong mong-ju


Ex Input:
joe the plumber, nickname of "samuel joseph "joe" wurzelbacher", (born december 3, 1973 in toledo, ohio) is an american commentator, motivational speaker and political activist.

Ex Output:
joe the plumber


Ex Input:
mostafa fathi (; born 12 may 1994) is an egyptian footballer.

Ex Output:

mostafa fathi