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: 'there are peoople standign next to a bike'. Replace the letter 'o' with 't' in the sentence.

Answer: there are pettple standign next tt a bike


Question: Sentence: 'a large group of people who are standing in a bed of a truck as it drives through water'. Replace the letter 't' with 'x' in the sentence.

Answer:
a large group of people who are sxanding in a bed of a xruck as ix drives xhrough waxer