instruction:
In this task, you need to replace a letter in the sentence with another given letter.
question:
Sentence: 'a small bird perched on a open window'. Replace the letter 'e' with 'r' in the sentence.
answer:
a small bird prrchrd on a oprn window


question:
Sentence: 'a seafood dish served over a bowl of white rice'. Replace the letter 'e' with 'u' in the sentence.
answer:
a suafood dish survud ovur a bowl of whitu ricu


question:
Sentence: 'six elephants gathered together outside around and in front of  trees'. Replace the letter 'a' with 's' in the sentence.
answer:

six elephsnts gsthered together outside sround snd in front of  trees