TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'a yellow street sign sitting on the side of a road'. Replace the letter 'a' with 'd' in the sentence.

SOLUTION: d yellow street sign sitting on the side of d rodd

PROBLEM: Sentence: 'a street pole stating three different street names and numbers'. Replace the letter 'm' with 't' in the sentence.

SOLUTION: a street pole stating three different street nates and nutbers

PROBLEM: Sentence: 'a man smiles as he holds a bright surf board'. Replace the letter 'i' with 's' in the sentence.

SOLUTION:
a man smsles as he holds a brsght surf board