Is the part where he says “to cash a check” a metaphor?
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Answer:
in a way yes, the figure compares going to the capital like cashing a deserved check: "We've come to our nation's capital to cash a check. " In this stance, cashing a check is using to refer to African Americans marching to the government during the Civil Rights Movement to get what US promised them.
Explanation:
A metaphor is a figure of speech that directly refers to one thing while mentioning another one. Metaphors are meant to establish clarity between ideas, or a link that connects them.