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: The man set up his camera to take sunset pictures at the beach. Sentence 2: A man is taking pictures of a lake.
2

Sentence 1: A dog shaking off water. Sentence 2: A dog shaking water off.
5

Sentence 1: The broader Standard & Poor's 500 Index <.SPX> was 0.46 points lower, or 0.05 percent, at 997.02. Sentence 2: The technology-laced Nasdaq Composite Index .IXIC was up 7.42 points, or 0.45 percent, at 1,653.44.

1