In this task, you need to replace a letter in the sentence with another given letter.
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Question: Sentence: 'a couple of brown bears walking across a lush green field'. Replace the letter 'w' with 'o' in the sentence.

Answer: a couple of broon bears oalking across a lush green field


Question: Sentence: 'a zebra is eating hay in a fenced enclosure'. Replace the letter 'e' with 'i' in the sentence.

Answer: a zibra is iating hay in a fincid inclosuri


Question: Sentence: 'a cat is curled up in a ball'. Replace the letter 'l' with 'j' in the sentence.

Answer:
a cat is curjed up in a bajj