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 beethoven house (german: beethoven-haus) in bonn, germany, is a memorial site, museum and cultural institution serving various purposes.

Ex Output:
beethoven house


Ex Input:
aerospace engineering is a field of engineering that specializes in vehicles that move in fluids.

Ex Output:
aerospace engineering


Ex Input:
pennywise is an american melodic hardcore band.

Ex Output:

pennywise