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

Example Input: Sentence: 'two zebras are snuggling at the zoo in their display area'. Replace the letter 'e' with 'z' in the sentence.
Example Output: two zzbras arz snuggling at thz zoo in thzir display arza

Example Input: Sentence: 'a skater looks ahead as he rides down a ramp'. Replace the letter 'n' with 'm' in the sentence.
Example Output: a skater looks ahead as he rides dowm a ramp

Example Input: Sentence: 'a man wearing a tie posing for a picture'. Replace the letter 'r' with 'u' in the sentence.
Example Output:
a man weauing a tie posing fou a pictuue