Evaluate the similarity between them and classify them into classes from 0-5 as follows:
0 : The two sentences are completely dissimilar.
1 : The two sentences are not equivalent, but are on the same topic.
2 : The two sentences are not equivalent, but share some details.
3 : The two sentences are roughly equivalent, but some important information differs/missing.
4 : The two sentences are mostly equivalent, but some unimportant details differ.
5 : The two sentences are completely equivalent, as they mean the same thing.

Sentence 1: A person is slicing an onion. Sentence 2: A cat is pooping into a toilet.
0

Sentence 1: a man walks two dogs on leashes down the street Sentence 2: A man walks two dogs in the city.
4

Sentence 1: A total of 17 cases have been confirmed in the southern city of Basra, the Organization said. Sentence 2: A total of 17 confirmed cases of cholera were reported yesterday by the World Health Organisation in the southern Iraqi city of Basra.

4