In this task, you're given a pair of sentences, sentence 1 and sentence 2, that agree with each other. Your job is to alter sentence 2 so that the pair contradict each other. Generated sentences must be short, with less than 15 words. New information can be introduced. Avoid using pronouns to confuse the subject of the sentence.

Example Input: Sentence 1: A child in a blue and red jacket is racking a pile of leaves. Sentence 2: A child in a jacket is racking.
Example Output: A child in a blue and red jacket is playing outside.

Example Input: Sentence 1: A man gets ready to throw a stick for his waiting dog. Sentence 2: The man is outdoors with his dog.
Example Output: A man is playing with a cat.

Example Input: Sentence 1: A runner dressed in black is preparing for a race. Sentence 2: A runner is preparing to run.
Example Output:
A house is on fire.