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.

Example Input: Sentence 1: A young boy in a brown jacket playing with snow. Sentence 2: Two dogs are playing in the snow.
Example Output: 1

Example Input: Sentence 1: A small white cat standing in a sink. Sentence 2: Grey and white cat sitting in bathroom sink.
Example Output: 4

Example Input: Sentence 1: A baby is laughing. Sentence 2: A baby is laughing and giggling.
Example Output:
4