TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'a man on a horse in riding gear looking onward'. Replace the letter 'o' with 'h' in the sentence.

SOLUTION: a man hn a hhrse in riding gear lhhking hnward

PROBLEM: Sentence: 'two men and a dog are standing beside a building'. Replace the letter 'b' with 'y' in the sentence.

SOLUTION: two men and a dog are standing yeside a yuilding

PROBLEM: Sentence: 'there is a clock tower on the building'. Replace the letter 'l' with 'p' in the sentence.

SOLUTION:
there is a cpock tower on the buipding