You will be given a definition of a task first, then some input of the task.
Indicate all the pronouns (they, them, you, he, his, her, you, it, etc.) present in the given sentence. If there are multiple such pronouns in a sentence, then list them in the order of their first appearance in the given sentence. If a pronoun appears multiple times in a sentence, list it only once.

john was doing research in the library when he heard a man humming and whistling. he was very annoyed.
Output:
he