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: An elderly woman rides a bicycle along a city street. Sentence 2: An elderly woman walking uphill crossing the street.
2

Sentence 1: A boy is pushing a van. Sentence 2: A person is slicing a tomato.
0

Sentence 1: South Africa president: Mandela is improving Sentence 2: Afghan president delays signing US deal

0