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: US Cannot 'Conclusively Determine' Chemical Weapons Use in Syria Sentence 2: U.S. Sees No Conclusive Evidence of Chemical Arms Use by Syria
Example Output: 5

Example Input: Sentence 1: fan stated the commission is primarily concerned with the term of future investment in taiwan. Sentence 2: fan stated the commission will ensure the commitments are upheld once the investments are under way.
Example Output: 2

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