TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'a double decker bus stopped outside a station on a street'. Replace the letter 'c' with 'y' in the sentence.

SOLUTION: a double deyker bus stopped outside a station on a street

PROBLEM: Sentence: 'the two boys are eating large carrots while sitting on a blanket'. Replace the letter 'a' with 'q' in the sentence.

SOLUTION: the two boys qre eqting lqrge cqrrots while sitting on q blqnket

PROBLEM: Sentence: 'a few people are in single file on their skies'. Replace the letter 'e' with 'c' in the sentence.

SOLUTION:
a fcw pcoplc arc in singlc filc on thcir skics