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: Someone standing on a snowy mountain, watching a plane. Sentence 2: A man stands on a mountain, watching a plane.

A: 4
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Q: Sentence 1: A cruise liner docked at the shoreline. Sentence 2: A cruise ship docked at shore.

A: 4
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Q: Sentence 1: The black bird is sitting on the ground. Sentence 2: A blackbird sitting on the ground.

A:
5
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