Final answer:
A metaphor is being used in the phrase 'a voice of thunder' to convey the idea of a powerful and commanding voice.
Explanation:
Metaphor is the figurative language technique being used in the phrase 'a voice of thunder.' A metaphor is a direct comparison between two unlike things, equating one with the other to convey a particular meaning or image. In this case, 'a voice of thunder' suggests that the voice is powerful, booming, and commanding, similar to the sound of thunder during a storm.
Learn more about Metaphor here:
https://brainly.com/question/42242543
