TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'a couple of men playing a  game of tennis'. Replace the letter 'n' with 'c' in the sentence.

SOLUTION: a couple of mec playicg a  game of teccis

PROBLEM: Sentence: 'a black velvety chair with chrome colored frame'. Replace the letter 'a' with 'z' in the sentence.

SOLUTION: z blzck velvety chzir with chrome colored frzme

PROBLEM: Sentence: 'a man who is skiing in the snow'. Replace the letter 'n' with 'q' in the sentence.

SOLUTION:
a maq who is skiiqg iq the sqow