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

Example Input: Sentence: 'a man walking a horse on a dirt track'. Replace the letter 't' with 's' in the sentence.
Example Output: a man walking a horse on a dirs srack

Example Input: Sentence: 'broccoli and cooked meat arranged on a plate'. Replace the letter 'c' with 'l' in the sentence.
Example Output: brolloli and looked meat arranged on a plate

Example Input: Sentence: 'a man juggling while standing on top of a sign riding a skateboard'. Replace the letter 'a' with 'w' in the sentence.
Example Output:
w mwn juggling while stwnding on top of w sign riding w skwtebowrd