Read the text "Civilizations", then listen to the tape and say what three pieces of information are missing in the written text.

CIVILIZATIONS
    The British archaeologist Gordon Childe worked out a theory explaining how a culture transforms into a civilization. He wrote that a civilization is characterized by the invention of writing, mathematics, monumental architecture, long-distance trade, wheeled carts, irrigation technology and some other features.
    Modern scholars say that a civilization has the following basic characteristics: political and religious structures and administration of the territories, a complex division of labour, with full-time artisans, soldiers, peasants and administrators.
    Anthropologists in the 19th century formulated a theory of cultural evolution in which they divided human development into three stages: savagery, barbarism and civilization. Speaking of civilizations they mentioned only a few peoples of antiquity. Within the past 100 years archaeological research has more than doubled the list.
    Historians have differed greatly in deciding how many civilizations there were in the past. Nowadays scholars study not only civilizations of the Western World going back to Ancient Greece and Rome but also the civilizations of Islam, Byzantium, India, China, Japan and the African kingdoms.