In this task, you need to replace a letter in the sentence with another given letter.
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Question: Sentence: 'a man on a surfboard riding on the waters waves'. Replace the letter 's' with 'k' in the sentence.

Answer: a man on a kurfboard riding on the waterk wavek


Question: Sentence: 'busy city street with pedestrians and cars with lights all around'. Replace the letter 'r' with 'k' in the sentence.

Answer: busy city stkeet with pedestkians and caks with lights all akound


Question: Sentence: 'a river ride bus with tourists traveling the water'. Replace the letter 's' with 'n' in the sentence.

Answer:
a river ride bun with tourintn traveling the water