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: 'traffic congestion with cars and an electric tram'. Replace the letter 'a' with 'k' in the sentence.

A: trkffic congestion with ckrs knd kn electric trkm
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Q: Sentence: 'a person holding a green plastic knife getting ready to cut a white cake'. Replace the letter 'a' with 'k' in the sentence.

A:
k person holding k green plkstic knife getting rekdy to cut k white ckke
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