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.

Example Input: yoshikazu goto ( , goto yoshikazu, born february 20, 1964) is a japanese professional athlete.
Example Output: yoshikazu goto

Example Input: hexameter is a metrical line of verse.
Example Output: hexameter

Example Input: the pentagon shopping centre (known locally as 'the pentagon') is a shopping centre in chatham, kent.
Example Output:
pentagon shopping centre