instruction:
In this task, you need to replace a letter in the sentence with another given letter.
question:
Sentence: 'a busy intersection with cars moving at night'. Replace the letter 's' with 'f' in the sentence.
answer:
a bufy interfection with carf moving at night


question:
Sentence: 'a man is standing on a snowboard, atop a mountain'. Replace the letter 'd' with 'u' in the sentence.
answer:
a man is stanuing on a snowboaru, atop a mountain


question:
Sentence: 'a group of people riding skis on a snowy surface'. Replace the letter 'p' with 'i' in the sentence.
answer:

a groui of ieoile riding skis on a snowy surface