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: The man is riding a horse. Sentence 2: A man is riding on a horse.
Example Output: 5

Example Input: Sentence 1: A small plane parked at an airfield with a cloudy sky overhead. Sentence 2: A small white plane parked in an airport on a cloudy day.
Example Output: 5

Example Input: Sentence 1: Your confusion doesn't make me a liar. Sentence 2: Then your confusion doesn't make me a liar either.
Example Output:
4