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 social democratic party of germany (german sozialdemokratische partei deutschlands or spd) is the oldest political party in germany that still exists, having been formed on 23 may 1863.

Ex Output:
social democratic party of germany


Ex Input:
rosenheim is a city in upper bavaria, germany.

Ex Output:
rosenheim


Ex Input:
kazuya maeda (born 8 september 1982) is a japanese football player.

Ex Output:

kazuya maeda