TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'two giraffe standing in an enclosure at the zoo next to a  tree'. Replace the letter 'n' with 'g' in the sentence.

SOLUTION: two giraffe stagdigg ig ag egclosure at the zoo gext to a  tree

PROBLEM: Sentence: 'a couple of kids are sitting in a field'. Replace the letter 't' with 'v' in the sentence.

SOLUTION: a couple of kids are sivving in a field

PROBLEM: Sentence: 'two young men pretending to joust in a kitchen'. Replace the letter 't' with 'm' in the sentence.

SOLUTION:
mwo young men premending mo jousm in a kimchen