In this task, you need to replace a letter in the sentence with another given letter.

Q: Sentence: 'a couple walking down a sidewalk next to some graffiti'. Replace the letter 'a' with 'y' in the sentence.

A: y couple wylking down y sidewylk next to some gryffiti
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Q: Sentence: 'two men and a dog are standing beside a building'. Replace the letter 'b' with 'y' in the sentence.

A: two men and a dog are standing yeside a yuilding
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Q: Sentence: 'two players shake hands over the net on a tennis court'. Replace the letter 't' with 'b' in the sentence.

A:
bwo players shake hands over bhe neb on a bennis courb
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