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

Example Input: Sentence: 'a police officer on a horse is riding down the street'. Replace the letter 'h' with 'a' in the sentence.
Example Output: a police officer on a aorse is riding down tae street

Example Input: Sentence: 'traffic congestion with cars and an electric tram'. Replace the letter 'a' with 'k' in the sentence.
Example Output: trkffic congestion with ckrs knd kn electric trkm

Example Input: Sentence: 'a display of many fruits for sale in an outdoor market'. Replace the letter 'y' with 'l' in the sentence.
Example Output:
a displal of manl fruits for sale in an outdoor market