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

Q: Sentence: 'a red hydrant is sitting on the sidewalk in the city'. Replace the letter 'n' with 'r' in the sentence.

A: a red hydrart is sittirg or the sidewalk ir the city
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Q: Sentence: 'a horse in a country field with woods in the background'. Replace the letter 'a' with 'i' in the sentence.

A: i horse in i country field with woods in the bickground
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Q: Sentence: 'three horses stand next to a street sign grazing'. Replace the letter 'a' with 's' in the sentence.

A:
three horses stsnd next to s street sign grszing
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