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

Ex Input:
Sentence: 'a herd of cattle standing on a lush green field'. Replace the letter 'g' with 'f' in the sentence.

Ex Output:
a herd of cattle standinf on a lush freen field

Ex Input:
Sentence: 'the child is throwing the frisbee through the hoop'. Replace the letter 't' with 'm' in the sentence.

Ex Output:
mhe child is mhrowing mhe frisbee mhrough mhe hoop

Ex Input:
Sentence: 'a boat traveling in the water near a castle, clock tower and a bridge'. Replace the letter 'h' with 'y' in the sentence.

Ex Output:
a boat traveling in tye water near a castle, clock tower and a bridge