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 drilled holes into the wood. Sentence 2: A man drills wood.
Example Output: 4

Example Input: Sentence 1: A man is running on the road. Sentence 2: A panda dog is running on the road.
Example Output: 2

Example Input: Sentence 1: south korea launches new bullet train reaching 300 kph. Sentence 2: south korea has had a bullet train system since the 1980s.
Example Output:
2