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: Man standing in front of silver train. Sentence 2: Man standing in front of a silver rail car.
Example Output: 4

Example Input: Sentence 1: saferworld team leader on transfer controls and small arms roy isbister stated-- the eu embargo prohibits direct or indirect supply of military equipment for use in myanmar. Sentence 2: saferworld team leader on transfer controls and small arms roy isbister stated that -- the eu embargo explicitly states that no military equipment should be supplied either directly or indirectly for use in myanmar.
Example Output: 5

Example Input: Sentence 1: A man walks toward a policeman standing in a crosswalk on a city street. Sentence 2: A policeman stands in a crosswalk in a city.
Example Output:
3