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.

Sentence 1: A rollerblader skates down a ramp with his arms in the air. Sentence 2: A rollerblader has his arms in the air.
The rollerblader is a girl.

Sentence 1: A man wearing no shirt climbs a steep cliff. Sentence 2: A shirtless man was climbing up the face of the cliff.
The lady was hiking the mountain.

Sentence 1: A brown dig and black dog are playing with a stuffed toy. Sentence 2: Two dogs are playing with each other.

A dog and a cat are playing with a stuffed toy.