In this task, you need to replace a letter in the sentence with another given letter.
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Question: Sentence: 'a yellow fire hydrant sitting on the sidewalk'. Replace the letter 'o' with 'd' in the sentence.

Answer: a yelldw fire hydrant sitting dn the sidewalk


Question: Sentence: 'the cargo train is headed to the next destination'. Replace the letter 'h' with 'x' in the sentence.

Answer: txe cargo train is xeaded to txe next destination


Question: Sentence: 'a wet polar bear walking along side some water'. Replace the letter 'r' with 'h' in the sentence.

Answer:
a wet polah beah walking along side some wateh