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

Q: Sentence: 'a crowd stands under a set of lights in the ceiling and one person holds up a cell phone'. Replace the letter 'r' with 'f' in the sentence.

A: a cfowd stands undef a set of lights in the ceiling and one pefson holds up a cell phone
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Q: Sentence: 'there is a purse on the floor with its contents spilled out'. Replace the letter 'd' with 'v' in the sentence.

A: there is a purse on the floor with its contents spillev out
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Q: Sentence: 'a red train moves over snowy rail road tracks'. Replace the letter 'v' with 'w' in the sentence.

A:
a red train mowes ower snowy rail road tracks
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