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

Example Input: Sentence: 'a large elephant standing outside beside a tree'. Replace the letter 'e' with 'y' in the sentence.
Example Output: a largy ylyphant standing outsidy bysidy a tryy

Example Input: Sentence: 'a giraffe sticks its tongue out in the air'. Replace the letter 'e' with 'l' in the sentence.
Example Output: a giraffl sticks its tongul out in thl air

Example Input: Sentence: 'the bottle of liquor and red book sip atop the counter of the bathroom'. Replace the letter 'a' with 'c' in the sentence.
Example Output:
the bottle of liquor cnd red book sip ctop the counter of the bcthroom