instruction:
In this task, you need to replace a letter in the sentence with another given letter.
question:
Sentence: 'a couple of brown bears walking across a lush green field'. Replace the letter 'w' with 'o' in the sentence.
answer:
a couple of broon bears oalking across a lush green field


question:
Sentence: 'a horse in a country field with woods in the background'. Replace the letter 'a' with 'i' in the sentence.
answer:
i horse in i country field with woods in the bickground


question:
Sentence: 'a woman standing next to a horse with a harness on'. Replace the letter 'o' with 'h' in the sentence.
answer:

a whman standing next th a hhrse with a harness hn