TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'a man stands in front of a plane on a take off strip'. Replace the letter 'n' with 'o' in the sentence.

SOLUTION: a mao staods io froot of a plaoe oo a take off strip

PROBLEM: Sentence: 'many street signs in front of a building while it is snowing'. Replace the letter 'r' with 'x' in the sentence.

SOLUTION: many stxeet signs in fxont of a building while it is snowing

PROBLEM: Sentence: 'a man holding a brown dog next to a rub'. Replace the letter 'o' with 'h' in the sentence.

SOLUTION:
a man hhlding a brhwn dhg next th a rub