<p>The people (A: sitting behind me) in the movie theater were talking throughout the film (B: and would) not keep (C: their voice) down even after being asked (D: todo so.) (E: No error)</p>
<p>The answer is C. I thought it'd be E.</p>
<p>Well, yeah, I thought about "their voices" for a split second before I changed my answer.</p>
<p>Seriously, does it have to be "voices" because we are referring to a plural noun-- "the people sitting behind me" in this case?</p>
<p>Thanx in advance :D</p>
<p>Yes “voices” must accompany a plural noun. I must admit I didn’t see the error the first time reading the sentence. </p>
<p>Although a phrase like “The voice of the people” sounds pretty grammatical. the “their” should be the real red flag.</p>
<p>@Kieran0696</p>
<p>Okay. From what I have solved so far, I inferred that there are certain cases when the principle of plural-plural is not applied.
For e.g.) She found eating cheese and drinking much water as the way of going on an ideal diet. (eating+drinking = the way)
Another example) The sound of the students. (like the one you’ve provided)</p>
<p>Can you verify these for me? Thank you so much anyways :D</p>