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: Feds move to require car-to-car safety communication Sentence 2: Guatemala overturns former dictator's genocide conviction
0

Sentence 1: Iraq Backs Egypt Crackdown on Morsi Supporters Sentence 2: Iraq backs Egypt crackdown on Mohamed Morsi supporters
5

Sentence 1: A man is rapidly chopping some mushrooms using a knife. Sentence 2: A person is quickly chopping mushrooms with a knife.

4