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.

Q: Sentence 1: A woman is riding an elephant. Sentence 2: A man is lifting himself.

A: 0
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Q: Sentence 1: three little boys cover themselves with bubbles. Sentence 2: Three children standing by a pool are covered in foam bubbles.

A: 4
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Q: Sentence 1: A sheep stands on a hillside. Sentence 2: A large sheep standing on a hill.

A:
4
****