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

Q: Sentence: 'a herd of black cattle grazing and lounging in a green field'. Replace the letter 'a' with 'q' in the sentence.

A: q herd of blqck cqttle grqzing qnd lounging in q green field
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Q: Sentence: 'a boy is sitting at a dinner table with his food'. Replace the letter 't' with 'r' in the sentence.

A: a boy is sirring ar a dinner rable wirh his food
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Q: Sentence: 'a mother elephant and her young calf stand by a pool at the zoo'. Replace the letter 'y' with 'a' in the sentence.

A:
a mother elephant and her aoung calf stand ba a pool at the zoo
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