In this task, you need to replace a letter in the sentence with another given letter.
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Question: Sentence: 'a guy looking at a tennis ball with a goofy look'. Replace the letter 'a' with 'x' in the sentence.

Answer: x guy looking xt x tennis bxll with x goofy look


Question: Sentence: 'many people gathered on a sunny day flying kites'. Replace the letter 'e' with 'm' in the sentence.

Answer: many pmoplm gathmrmd on a sunny day flying kitms


Question: Sentence: 'three polar bears are walking amongst some rocks'. Replace the letter 'r' with 'j' in the sentence.

Answer:
thjee polaj beajs aje walking amongst some jocks