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 person is driving an all-terrain vehicle through a muddy course. Sentence 2: persons first time in ATV
person drives ATV

Sentence 1: Three bicyclists riding down a steep course wearing helmets. Sentence 2: the bicyclists are being careful down the steep course.
The bicyclists are  wearing helmets.

Sentence 1: Two firemen getting ready to get onto a firetruck. Sentence 2: Two firemen are about to put out a fire.

Two firemen are about to ride on a firetruck.