Final answer:
Martin Luther King Jr. is using the rhetorical appeal of repetition when he repeats the words "I have a dream" in his speech. The use of repetition has a powerful effect on the audience.
Step-by-step explanation:
Martin Luther King Jr. is using the rhetorical appeal of repetition when he repeats the words "I have a dream" in his speech. This is an example of anaphora, which is the repetition of a word or phrase at the beginning of successive clauses or sentences.
The use of repetition has a powerful effect on the audience. It creates a sense of rhythm and emphasis, making the words more memorable and impactful. By repeating the phrase "I have a dream," King reinforces his vision for racial equality and inspires hope and unity among the listeners.