In this task, you need to replace a letter in the sentence with another given letter.
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Question: Sentence: 'a train traveling through a dark tunnel next to green brush.'. Replace the letter 'r' with 'e' in the sentence.

Answer: a teain teaveling theough a daek tunnel next to geeen beush.


Question: Sentence: 'two children who are standing next to a white fire hydrant'. Replace the letter 't' with 'r' in the sentence.

Answer: rwo children who are sranding nexr ro a whire fire hydranr


Question: Sentence: 'a teddy bear is sitting on a pile of stuffed animals'. Replace the letter 'l' with 'j' in the sentence.

Answer:
a teddy bear is sitting on a pije of stuffed animajs