TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'a shot looks down on a person riding a long board'. Replace the letter 'o' with 'u' in the sentence.

SOLUTION: a shut luuks duwn un a persun riding a lung buard

PROBLEM: Sentence: 'a giraffe looking over a fence and another reaching over the fence'. Replace the letter 'l' with 'h' in the sentence.

SOLUTION: a giraffe hooking over a fence and another reaching over the fence

PROBLEM: Sentence: 'sheep waking along a road near stone houses'. Replace the letter 's' with 'f' in the sentence.

SOLUTION:
fheep waking along a road near ftone houfef