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

Example Input: Sentence: 'a city street with cars and busses near buildings'. Replace the letter 'e' with 'd' in the sentence.
Example Output: a city strddt with cars and bussds ndar buildings

Example Input: Sentence: 'a group of three giraffes standing around a fence'. Replace the letter 't' with 'a' in the sentence.
Example Output: a group of ahree giraffes saanding around a fence

Example Input: Sentence: 'a person being down on one knee playing tennis'. Replace the letter 'n' with 'v' in the sentence.
Example Output:
a persov beivg dowv ov ove kvee playivg tevvis