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: Black train on train tracks. Sentence 2: A train on the train tracks.

A: 4
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Q: Sentence 1: A man is playing an electronic keyboard. Sentence 2: A band is playing instruments.

A: 1
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Q: Sentence 1: A brown and white dog sits on a floral-patterned chair. Sentence 2: A small orange and white dog with a collar and a bell relaxes on a flower print pillow.

A:
2
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