instruction:
In this task, you need to replace a letter in the sentence with another given letter.
question:
Sentence: 'a small train is on the tracks by a house'. Replace the letter 'l' with 'x' in the sentence.
answer:
a smaxx train is on the tracks by a house


question:
Sentence: 'the child is throwing the frisbee through the hoop'. Replace the letter 't' with 'm' in the sentence.
answer:
mhe child is mhrowing mhe frisbee mhrough mhe hoop


question:
Sentence: 'a shaggy brown dog has a red ball in it's mouth'. Replace the letter 'l' with 'o' in the sentence.
answer:

a shaggy brown dog has a red baoo in it's mouth