Final answer:
The subject of the sentence 'The HUNTERS will return on Monday' is 'the hunters,' which is the part of the sentence performing the action.
Step-by-step explanation:
The subject of the sentence "The HUNTERS will return on Monday" is 'the hunters.' In English grammar, the subject of a sentence is the person, place, thing, or idea that is doing or being something.
In this case, 'the hunters' are the ones performing the action of returning. As this explanation pertains to the understanding and identification of grammatical constructs, it falls under the English subject category.
The provided context in the form of book excerpts gives a clue that this question is likely from a literature or language arts class, which typically falls into the high school grade range.