instruction:
In this task, you need to replace a letter in the sentence with another given letter.
question:
Sentence: 'a tennis racket is sitting in the middle of a tennis field'. Replace the letter 'i' with 'f' in the sentence.
answer:
a tennfs racket fs sfttfng fn the mfddle of a tennfs ffeld


question:
Sentence: 'a horse in a country field with woods in the background'. Replace the letter 'a' with 'i' in the sentence.
answer:
i horse in i country field with woods in the bickground


question:
Sentence: 'a young boy swings his bat as the baseball comes flying towards him'. Replace the letter 'y' with 'r' in the sentence.
answer:

a roung bor swings his bat as the baseball comes flring towards him