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

[Q]: Sentence: 'a blue and white train is coming down some tracks'. Replace the letter 'b' with 'u' in the sentence.
[A]: a ulue and white train is coming down some tracks


[Q]: Sentence: 'a close shot of a stop sign near a building'. Replace the letter 'b' with 'u' in the sentence.
[A]: a close shot of a stop sign near a uuilding


[Q]: Sentence: 'a woman is laying in a bed in the dark'. Replace the letter 'd' with 'h' in the sentence.
[A]:
a woman is laying in a beh in the hark