In this task, you need to replace a letter in the sentence with another given letter.
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Question: Sentence: 'some brown black and white horses clouds and rocks'. Replace the letter 'a' with 'n' in the sentence.

Answer: some brown blnck nnd white horses clouds nnd rocks


Question: Sentence: 'a close up of a grassy beach showing an umbrella and wind board'. Replace the letter 'a' with 'f' in the sentence.

Answer: f close up of f grfssy befch showing fn umbrellf fnd wind bofrd


Question: Sentence: 'a young man turns on his skateboard mid-air over the concrete steps'. Replace the letter 'r' with 'u' in the sentence.

Answer:
a young man tuuns on his skateboaud mid-aiu oveu the concuete steps