In this task, you need to replace a letter in the sentence with another given letter.
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Question: Sentence: 'an old rusty car sits outside of an old building'. Replace the letter 'o' with 'r' in the sentence.

Answer: an rld rusty car sits rutside rf an rld building

Question: Sentence: 'a tennis player throwing a ball at the ground'. Replace the letter 'r' with 'f' in the sentence.

Answer: a tennis playef thfowing a ball at the gfound

Question: Sentence: 'the snowboarder is just starting his run down the slope'. Replace the letter 'j' with 'c' in the sentence.

Answer:
the snowboarder is cust starting his run down the slope