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 climber is standing on the rock face next to the pink rope. Sentence 2: The children are running in the snow with fences in the background.
Example Output: 0

Example Input: Sentence 1: Egypt votes on final day of presidential election Sentence 2: Polls open in France for presidential election
Example Output: 1

Example Input: Sentence 1: Yeah, I don't think this is that controversial either. Sentence 2: I don't think what she's saying is that controversial.
Example Output:
4