TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'a mouse and keyboard sitting on a wooden desk'. Replace the letter 'a' with 'n' in the sentence.

SOLUTION: n mouse nnd keybonrd sitting on n wooden desk

PROBLEM: Sentence: 'two stuffed animal bears  sitting next to a candy bar and a flower pot on a table'. Replace the letter 'd' with 'w' in the sentence.

SOLUTION: two stuffew animal bears  sitting next to a canwy bar anw a flower pot on a table

PROBLEM: Sentence: 'an airplane moves through the skies above a snowy mountain range'. Replace the letter 'l' with 's' in the sentence.

SOLUTION:
an airpsane moves through the skies above a snowy mountain range