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

Example Input: Sentence: 'horses drink and graze the field and water'. Replace the letter 'i' with 'c' in the sentence.
Example Output: horses drcnk and graze the fceld and water

Example Input: Sentence: 'the two zebras standing out in the field'. Replace the letter 'h' with 'i' in the sentence.
Example Output: tie two zebras standing out in tie field

Example Input: Sentence: 'a few little kids that are on a big bed'. Replace the letter 'h' with 'm' in the sentence.
Example Output:
a few little kids tmat are on a big bed