Answer and Explanation:
Petrarch uses metaphors in his poem to intensify the idealization of the beloved woman, the loneliness of not getting her and even how the speaker of the poem feels about an unattainable love. The use of a figure of speech allows Petrarch to associate love with intense, yet subjective and poetic concepts, enriching his text and promoting a broad understanding of the feelings he wishes to convey, all involving love and the impossibility of having it.
An example of the use of metaphor can be seen when Petrarch characterizes the beloved woman, stating that she is able to "make a paradise on earth" and that she is "the light I loved so much." In addition, he uses metaphor as showing how sad it feels to not reach love, when he says he feels like "In a great storm on an unprotected raft."