填空题

There seems never to have been a civilization without toys, 【B1】 when and how they developed is unknown. They probably came 【B2】 just to give children something to do. In the ancient world, as is today, most boys played with some kinds of toys and most girls 【B3】 other. In societies where social roles are 【B4】 determined boys pattern their play 【B5】 the activities of their fathers and girls after the tasks of their mothers. This is true because boys and girls are being 【B6】 . even in play, to step into the roles and responsibilities of the 【B7】 world. What is 【B8】 about the history of toys is not so much how they changed over the centuries 【B9】 how much they have remained the same. The 【B10】 have been mostly in terms of craftsmanship, mechanics, and technology. It is the universality of toys with regard to their development in all part of the world and their persistence to the present 【B11】 is amazing. In Egypt, the Americas, China, Japan and among the Arctic peoples, generally the same kinds of toys appeared. 【B12】 depended on local customs and ways of life because toys 【B13】 their surroundings. 【B14】 . nearly every civilization had dolls, little weapons, toy soldiers, tiny animals and vehicles. Because toys can be generally regarded as a kind of art 【B15】 . they have not been 【B16】 to technological leaps that characterize inventions for adult use. The 【B17】 from the wheel to the oxcart to the automobile is a direct line of ascent. The progress from a rattle used by a baby in 3000 BC to one used by an 【B18】 today, however, is not characterized by inventiveness. Each rattle is the product of the 【B19】 tastes of the times and subject to the 【B20】 of available materials.