TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
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: 'a polar bear relaxing in a man-made pool'. Replace the letter 'r' with 'x' in the sentence.

SOLUTION: a polax beax xelaxing in a man-made pool

PROBLEM: Sentence: 'a group of people standing on top of a snow covered field'. Replace the letter 'f' with 'g' in the sentence.

SOLUTION:
a group og people standing on top og a snow covered gield