TASK DEFINITION: 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.
PROBLEM: central plaza is a skyscraper in hong kong.

SOLUTION: central plaza

PROBLEM: silliness is when a person acts like a fool, or shows a lack of good sense or judgment.

SOLUTION: silliness

PROBLEM: cloud gate is a public sculpture by indian-born british artist sir anish kapoor.

SOLUTION:
cloud gate