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: Syrian opposition offers Assad truce in Homs for duration of Ramadan Sentence 2: Syrian opposition offers Assad's forces truce for duration of Ramadan
Example Output: 5

Example Input: Sentence 1: Two die in Syria violence after UN monitors land Sentence 2: Two year doping ban for Contador
Example Output: 0

Example Input: Sentence 1: A young boy riding a bike on a brick road Sentence 2: A person does tricks on a bike on a ramp surrounded by trees.
Example Output:
2