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: Someone standing on a snowy mountain, watching a plane. Sentence 2: A man stands on a mountain, watching a plane.
Example Output: 4

Example Input: Sentence 1: A woman cracks two eggs into a glass bowl. Sentence 2: A woman is cracking an egg into a bowl.
Example Output: 4

Example Input: Sentence 1: Obama set to speak on Syria from White House at 1:15 p.m. EDT Sentence 2: Obama to deliver statement on Syria at White House at 1:15 PM
Example Output:
5