In this task, you need to replace a letter in the sentence with another given letter.

Sentence: 'a couple of white street signs sitting on top of a pole'. Replace the letter 'n' with 't' in the sentence.
a couple of white street sigts sittitg ot top of a pole

Sentence: 'a couple of kids laying in bed together'. Replace the letter 'o' with 'v' in the sentence.
a cvuple vf kids laying in bed tvgether

Sentence: 'two horses on their hind legs in a field of grass'. Replace the letter 'n' with 'j' in the sentence.
two horses oj their hijd legs ij a field of grass