In contrasting "darkness" with "radiantly," Shelley emphasizes that life is fleeting but exciting, as shown in the first answer.
Shelley shows how life is contradictory and fickle by showing that it is dark and radiant at the same time. With this, she reinforces the idea that life is exciting and that even with obscure things, it should be explored.
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https://brainly.com/question/26356666