1 . 阅读下面材料,在空白处填入 1 个适当的单词或括号内单词的正确形式。
A group of students from England, who are interested in archaeology, have come to the Zhoukoudian caves for a visit. An archaeologist 1 (warm) gives them a brief introduction 2 the life and habits of the earliest people there.
Early people lived in caves and they made fires in the centre of caves 3 (keep) themselves warm, cook the food and scare their enemies away, such as tigers and bears. They might have kept the fire burning all winter because layers of ash almost six metres thick have been excavated.
Early people did wear clothes made from animal skins. They used sharpened stone 4 (tool) to cut up animals and remove their skins. Smaller scrapers 5 (use) to remove the fat and meat from the skin. Finally using needles 6 (make) of animal bones, they would sew the pieces together.
Early people also paid attention to their 7 (appear) and wore necklaces. Some of the necklace beads were made of animal bones but some were made of shells, 8 told us that all the fields around Zhoukoudian caves used to be part of 9 large shallow lake. They moved around, following the herds of animals. They didn’t grow their own crops, but picked fruit when it 10 (ripen) and hunted animals.