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

Example Input: Sentence: 'commuter trains on tracks next to paved platform'. Replace the letter 'm' with 'w' in the sentence.
Example Output: cowwuter trains on tracks next to paved platforw

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 car drives through a street in a suburban neighborhood'. Replace the letter 'r' with 'f' in the sentence.
Example Output:
a caf dfives thfough a stfeet in a subufban neighbofhood