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: Italy soldiers die in Afghanistan Sentence 2: Two UK Soldiers Killed In Afghanistan
Example Output: 1

Example Input: Sentence 1: A monkey pulls the tail of a dog. Sentence 2: A monkey is teasing a dog at the zoo.
Example Output: 3

Example Input: Sentence 1: Microsoft fell 5 percent before the open to $27.45 from Thursday's close of $28.91. Sentence 2: Shares in Microsoft slipped 4.7 percent in after-hours trade to $27.54 from a Nasdaq close of $28.91.
Example Output:
3