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.

Input: Consider Input: The analyst asked the secretary to book a flight because she knows how to do it .

Output: the, secretary, she


Input: Consider Input: The construction worker stared at the teacher because she entered the construction zone .

Output: the, teacher, she


Input: Consider Input: The physician told the nurse that she can go back home .


Output: the, nurse, she