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 river clyde (, ]) is a river in scotland.

Ex Output:
river clyde


Ex Input:
laurie cunningham is a former football player.

Ex Output:
laurie cunningham


Ex Input:
arabesque is an artistic decoration.

Ex Output:

arabesque