instruction:
In this task, you need to replace a letter in the sentence with another given letter.
question:
Sentence: 'a herd of zebra stand together and eat grass'. Replace the letter 'n' with 'r' in the sentence.
answer:
a herd of zebra stard together ard eat grass


question:
Sentence: 'a few zebras that are next to each other'. Replace the letter 'o' with 'u' in the sentence.
answer:
a few zebras that are next tu each uther


question:
Sentence: 'an older couple cross country skiing in the woods'. Replace the letter 'e' with 'm' in the sentence.
answer:

an oldmr couplm cross country skiing in thm woods