Final answer:
An example of an allusion in Martin Luther King, Jr.'s "I Have a Dream" speech is the phrase "let freedom ring from every hill." It alludes to the traditional song "America."
Step-by-step explanation:
An allusion is a figure of speech that refers to a well-known person, event, or piece of literature. In Martin Luther King, Jr.'s "I Have a Dream" speech, the phrase "let freedom ring from every hill" is an example of an allusion. This phrase alludes to the traditional song "America" in which the line "let freedom ring" is repeated. The allusion in King's speech conveys the idea of freedom spreading across the nation.
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