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.

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.
5

Sentence 1: The man added vegetables to the broth in the pot. Sentence 2: A man is adding sliced vegetables to a cooking bowl with water.
3

Sentence 1: Scuba diver submerged in water. Sentence 2: The scuba diver is underwater.

5