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

Example Input: Sentence: 'red helicopter with landing wheels flying in the sky'. Replace the letter 'h' with 'y' in the sentence.
Example Output: red yelicopter wity landing wyeels flying in tye sky

Example Input: Sentence: 'a close up of a train on train tracks at night'. Replace the letter 'n' with 'm' in the sentence.
Example Output: a close up of a traim om traim tracks at might

Example Input: Sentence: 'a man carrying a surfboard at the edge of the water'. Replace the letter 'a' with 'j' in the sentence.
Example Output:
j mjn cjrrying j surfbojrd jt the edge of the wjter