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: various positions is the seventh studio album by leonard cohen, it was released in december 1984 (and february 1985).
Example Output: various positions

Example Input: a hamburger is a type of sandwich with cooked ground meat between the two halves of a bun.
Example Output: hamburger

Example Input: colomieu is a commune.
Example Output:
colomieu