TASK DEFINITION: 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.
PROBLEM: Sentence 1: Four men, three of whom are wearing prayer caps, are sitting on a blue and olive green patterned mat. Sentence 2: People are praying on a mat.

SOLUTION: People are sitting on a mat.

PROBLEM: Sentence 1: A door in a tall concrete wall Sentence 2: A door in a wall of at stone building.

SOLUTION: A door in a wall.

PROBLEM: Sentence 1: A man in a white shirt is working on a rooftop. Sentence 2: A man is roofing.

SOLUTION:
A man is clothed on a rooftop.