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: A monkey pulls the tail of a dog. Sentence 2: A monkey is teasing a dog at the zoo.
3

Sentence 1: Someone is playing piano. Sentence 2: A person is playing a keyboard piano.
4

Sentence 1: A cat stares into the camera. Sentence 2: A cat addresses the camera.

3