TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'some tracks for a rail way system near a building'. Replace the letter 'a' with 'h' in the sentence.

SOLUTION: some trhcks for h rhil why system nehr h building

PROBLEM: Sentence: 'a person that is sitting under an umbrella'. Replace the letter 'a' with 'l' in the sentence.

SOLUTION: l person thlt is sitting under ln umbrelll

PROBLEM: Sentence: 'a man punching another man in the genitals'. Replace the letter 'n' with 'z' in the sentence.

SOLUTION:
a maz puzchizg azother maz iz the gezitals