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 brown dogs licks its black nose. Sentence 2: The brown dog has a black nose.
The yellow dog is licking it's nose.

Sentence 1: African children are being taught by a teacher. Sentence 2: A group of students are listening to their teacher in Africa.
A group of students play at recess.

Sentence 1: A skateboarder examines the Hollywood Walk of Fame. Sentence 2: A person looking at the Walk of Fame.

A person working hard.