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

[Q]: Sentence: 'a couple of horses with carriages at a building'. Replace the letter 'u' with 'm' in the sentence.
[A]: a comple of horses with carriages at a bmilding


[Q]: Sentence: 'the door of the refrigerator has many magnets and small pictures on it'. Replace the letter 's' with 'z' in the sentence.
[A]: the door of the refrigerator haz many magnetz and zmall picturez on it


[Q]: Sentence: 'an elephant is grabbing onto a tree branch'. Replace the letter 'a' with 'x' in the sentence.
[A]:
xn elephxnt is grxbbing onto x tree brxnch