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

Example Input: Sentence: 'lose up of various trays of croissants and muffins'. Replace the letter 'n' with 'f' in the sentence.
Example Output: lose up of various trays of croissafts afd muffifs

Example Input: Sentence: 'a cat with a pink bow sits underneath something silver'. Replace the letter 'h' with 'n' in the sentence.
Example Output: a cat witn a pink bow sits underneatn sometning silver

Example Input: Sentence: 'young boys playing baseball in a dirt field'. Replace the letter 'p' with 's' in the sentence.
Example Output:
young boys slaying baseball in a dirt field