instruction:
In this task, you need to replace a letter in the sentence with another given letter.
question:
Sentence: 'a group of three giraffes standing around a fence'. Replace the letter 't' with 'a' in the sentence.
answer:
a group of ahree giraffes saanding around a fence


question:
Sentence: 'a zebra patterned set of hair brushes sitting on each other'. Replace the letter 'r' with 'a' in the sentence.
answer:
a zebaa patteaned set of haia baushes sitting on each othea


question:
Sentence: 'many street signs in front of a building while it is snowing'. Replace the letter 'r' with 'x' in the sentence.
answer:

many stxeet signs in fxont of a building while it is snowing