TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'a buddha statue sitting under a cat umbrella'. Replace the letter 'c' with 'h' in the sentence.

SOLUTION: a buddha statue sitting under a hat umbrella

PROBLEM: Sentence: 'a red train sitting at an empty station'. Replace the letter 'i' with 'h' in the sentence.

SOLUTION: a red trahn shtthng at an empty stathon

PROBLEM: Sentence: 'a young man sits on a wall using a cell phone'. Replace the letter 's' with 't' in the sentence.

SOLUTION:
a young man titt on a wall uting a cell phone