The cause<span> of </span>death<span> remains unknown despite a careful review of the medical history, scene investigation, and autopsy.</span>
Ok, the speaker is a man who lost his lover. He's depressed. a Raven flies in and repeatedly says "never more." the speaker asks him over and over depressing questions almost to make himself feel worse. that's the best I can give you.
My best guess would be a gerund phrase because the -ing verb is at the beginning of the sentence, thus making it a noun
