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

[EX Q]: Sentence: 'a man who is surfing in a wave in the ocean'. Replace the letter 'a' with 'u' in the sentence.
[EX A]: u mun who is surfing in u wuve in the oceun

[EX Q]: Sentence: 'a small train is on the tracks by a house'. Replace the letter 'l' with 'x' in the sentence.
[EX A]: a smaxx train is on the tracks by a house

[EX Q]: Sentence: 'two white and black sheep standing together in a field'. Replace the letter 'r' with 'k' in the sentence.
[EX A]:
two white and black sheep standing togethek in a field