Abacus

算盘( Abacus)是一种手动操作计算辅助工具形式。它起源于中国，是中国古代的一项重要发明。现在计算机已经很普遍了，但仍可以使用算盘( Abacus)来帮助小孩理解数字。 此模型可以完全靠自身卡扣相互卡住，组建完成后，很坚固。 Abacus is a form of manual calculation aid tool. It originated in China and is an important invention in ancient China.Computers are now very common, but abacus can still be used to help children understand numbers.This model can fully rely on its own buckles to lock each other, and after assembly, it is very sturdy. 按下图顺序组装即可： Assemble in the order shown in the following diagram：