A group of students came to Zhoukoudian for a          . An archaeologist showed them round. He told them it was here that they found           of some of the earliest people who lived in this           of the world, and it was reasonable to           they had lived in these caves, regardless of the cold. We had discovered           in the centre of the caves. It seemed that they might have used           stone tools to cut           the animal and          their skin to sew the pieces together. Maybe there was           between early peoples. They didn't          their own crops, but picked fruit and killed animals.