Q: In this task, you're given a pair of sentences, sentence 1 and sentence 2. Your job is to determine if the two sentences clearly agree/disagree with each other, or if this can't be determined. Indicate your answer as yes or no respectively.
Sentence 1: After the town was abandoned to malaria and Arab invaders in the ninth century, the monuments disappeared under wild vegetation until their rediscovery 900 years later. Sentence 2: Arab invaders contributed to the downfall of this town 900 years ago.
A:
yes