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

Example Input: Sentence: 'a living room with an orange couch and green decorations'. Replace the letter 'c' with 'm' in the sentence.
Example Output: a living room with an orange moumh and green demorations

Example Input: Sentence: 'a group of people riding skis on a snowy surface'. Replace the letter 'p' with 'i' in the sentence.
Example Output: a groui of ieoile riding skis on a snowy surface

Example Input: Sentence: 'a man is lying on the floor with his calculator and briefcase preparing to work'. Replace the letter 'o' with 'q' in the sentence.
Example Output:
a man is lying qn the flqqr with his calculatqr and briefcase preparing tq wqrk