This task is about identifying the subject of a given sentence. The subject of a sentence is the person, place, or thing that is performing the action of the sentence. The subject represents what or whom the sentence is about. Each sentence in this task is guaranteed to contain a single subject. The input is a sentence and the output is the identified subject of that sentence.

Example Input: The Battle of Antietam took place during the American Civil War.
Example Output: Battle of Antietam

Example Input: Cortex assembly for genome and date
Example Output: Cortex

Example Input: Aenir was written by Garth Nix.
Example Output:
Aenir