古代的有偿借书风俗四川夹江第二空军飞行学院王器利古人借书，有一个独特的风俗，那就是需要一定的酬谢品，古人称之为“双”。由于这种风俗，其性质有点类似于我们现在的有偿借阅，因此，一定程度上可以说双这种风俗开创了有偿服务的先河。那么，双是怎么一回事呢？我国... The ancient custom loan books Sichuan Jiajiang Second Air Force Flying Academy Wang Lixian borrowed books, there is a unique custom, that is, you need some reward, the ancients called “double.” As a result of this custom, its nature is somewhat similar to our present paid loan, so to some extent it can be argued that this custom created a precedent for paid services. So what is the double thing? My country ...