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

Q: Sentence: 'a book shelf full of books and nick nacks '. Replace the letter 'o' with 'm' in the sentence.

A: a bmmk shelf full mf bmmks and nick nacks 
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Q: Sentence: 'there is a big room with furniture and items inside'. Replace the letter 'e' with 'k' in the sentence.

A: thkrk is a big room with furniturk and itkms insidk
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Q: Sentence: 'a pitcher, catcher, batter and umpire in a baseball game'. Replace the letter 'i' with 'b' in the sentence.

A:
a pbtcher, catcher, batter and umpbre bn a baseball game
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