Oxymoron because <span>a figure of speech in which apparently contradictory terms appear in conjunctions</span>
George Herbert, "The Collar" - cacophony
John Donne, Sonnet 10 - paradox
John Donne, "The Sun Rising" - hyperbole
Andrew Marvell, "To His Coy Mistress" - carpe diem
John Donne, "The Flea" - synecdoche
that's tuff because ether answer won't make sense
All the sentences in a paragraph should be unified and coherent.
Answer: sentences
From the topic sentence to the concluding sentence, they need to be unified and coherent for the writer to truly get their point across as it was intended.
Hope this helps! :)