In this task, you will be given a sentence, and you need to identify the set of coreference words. Coreferences are generally a set of words in the text that refer to the same person or thing. Your output set of coreference words must be strictly present in the given input sentence. Do not use any outside knowledge to create the set of coreference words. If there is a 'the' article before the person or thing you should include 'the' as well. Please separate the coreference words by commas in the output.

Example Input: The salesperson chatted with the cleaner because she wanted to buy a vacuum .
Example Output: the, cleaner, she

Example Input: The guard asked the librarian to leave because it was late and she looked really tired .
Example Output: the, librarian, she

Example Input: The sheriff trusts the assistant because he is a trustful person .
Example Output:
The, sheriff, he