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 toy train is striking a toy car. Sentence 2: A toy train strikes a toy car.
Example Output: 5

Example Input: Sentence 1: During the same quarter last year, EDS declared a profit of $354 million, or 72 cents per share. Sentence 2: EDS reported a first-quarter loss of $126 million, or 26 cents per share.
Example Output: 2

Example Input: Sentence 1: 'Scores of bodies' found in Syria Sentence 2: Eight more bodies found on ship
Example Output:
1