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.
--------
Question: corrosion is the breakdown of materials due to chemical reactions.

Answer: corrosion


Question: the wrigley building (400-410 north michigan avenue, near north side, chicago, illinois) is a skyscraper in chicago.

Answer: wrigley building


Question: emiliano moretti (born 11 june 1981) is an italian football player.

Answer:
emiliano moretti