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

Example Input: Sentence: 'a dog wearing a pink life jacket sitting on a surf board in the ocean'. Replace the letter 'c' with 'y' in the sentence.
Example Output: a dog wearing a pink life jayket sitting on a surf board in the oyean

Example Input: Sentence: 'a person is looking out of a large window'. Replace the letter 'o' with 'p' in the sentence.
Example Output: a perspn is lppking put pf a large windpw

Example Input: Sentence: 'people are skiing with kites in the ocean'. Replace the letter 'c' with 'i' in the sentence.
Example Output:
people are skiing with kites in the oiean