(A) Metonymy → (III) I enjoy reading Shakespeare
Metonymy is a figure of speech in which something is referred to by the name of something closely associated with it.
"I enjoy reading Shakespeare" refers to reading Shakespeare's works, using the author’s name to represent his writings.
(B) Paradox → (I) Tell me not, Sweet, I am unkind
Paradox is a statement that seems self-contradictory but may contain an underlying truth.
"Tell me not, Sweet, I am unkind" is paradoxical because the speaker claims not to be unkind, even though the action (leaving) might be seen as unkind.
(C) Personification → (II) Busy old fool, unruly Sun
Personification involves giving human traits to non-human things.
"Busy old fool, unruly Sun" gives the sun human characteristics by addressing it as a busy and foolish being.
(D) Metaphor → (IV) The river snakes its way through the mountains
Metaphor is a figure of speech that directly compares two unlike things without using "like" or "as."
"The river snakes its way" compares the river’s winding path to the movement of a snake without explicitly stating the comparison with "like" or "as."