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

Example Input: Sentence: 'a person and a dog are on a bench'. Replace the letter 'e' with 'r' in the sentence.
Example Output: a prrson and a dog arr on a brnch

Example Input: Sentence: 'a woman is holding a bowl of green brocolli'. Replace the letter 'o' with 'w' in the sentence.
Example Output: a wwman is hwlding a bwwl wf green brwcwlli

Example Input: Sentence: 'a professional baseball player following through on a pitch'. Replace the letter 'a' with 'd' in the sentence.
Example Output:
d professiondl bdsebdll pldyer following through on d pitch