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.
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Question: Sentence 1: But the FBI never kept tabs on al-Bayoumi - even though it had received information that he was a Saudi agent, the document says. Sentence 2: But the bureau never kept tabs on al-Bayoumi—despite receiving prior information he was a secret Saudi agent, the report says.

Answer: 5


Question: Sentence 1: Could be a lot of things. Sentence 2: Could be a simple mistake.

Answer: 2


Question: Sentence 1: A mostly black train on a track. Sentence 2: A car parked in front of train tracks.

Answer:
1