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: Egypt's opposition criticizes president's speech Sentence 2: Pakistan's opposition party boycotts presidential elections
Example Output: 0

Example Input: Sentence 1: The man set up his camera to take sunset pictures at the beach. Sentence 2: A man is taking pictures of a lake.
Example Output: 2

Example Input: Sentence 1: Afghans flock to colleges, even as Taliban loom Sentence 2: Afghan District Governor Defects To Taliban
Example Output:
1