TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'a close up of a grassy beach showing an umbrella and wind board'. Replace the letter 'a' with 'f' in the sentence.

SOLUTION: f close up of f grfssy befch showing fn umbrellf fnd wind bofrd

PROBLEM: Sentence: 'a young boy in a shopping cart looking at tooth brushes'. Replace the letter 'o' with 'r' in the sentence.

SOLUTION: a yrung bry in a shrpping cart lrrking at trrth brushes

PROBLEM: Sentence: 'two men riding paddle skate boards down a road'. Replace the letter 'b' with 'q' in the sentence.

SOLUTION:
two men riding paddle skate qoards down a road