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.

Example Input: Sentence 1: A girl is styling her hair. Sentence 2: A girl is filing her nails.
Example Output: 1

Example Input: Sentence 1: A man is cutting a paper. Sentence 2: A person is tearing paper.
Example Output: 3

Example Input: Sentence 1: berlin will host top-level meetings in october to save key european arms control treaty conventional forces in europe (cfe). Sentence 2: russia suspended its participation in a key european arms control treaty that governs deployment of troops in europe.
Example Output:
2