In this task, you're given a pair of sentences, sentence 1 and sentence 2, that neither agree with nor contradict each other. Your job is to alter sentence 2 so that the pair clearly 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.

Sentence 1: A young man sits with his elbows on his legs while he reads a book. Sentence 2: A teenager is flipping through a book in the library.
A book reader is engrossed in his book.

Sentence 1: A young man using a notepad and pen to diagram an image. Sentence 2: A young man using a red pen with a notepad.
A young man using a pen and notepad.

Sentence 1: Firefighters and policemen are responding to the scene of a car accident. Sentence 2: Firefighters and policemen are responding to the scene of a car accident caused by bad brakes.

A car accident has police and firefighters responding to it.