zhè / běn / shū / jiè / shào / le / hēi / wǔ / lèi / zhè / yī / lì / shǐ / gài / niàn / de / xíng / chéng / bèi / jǐng这本书介绍了黑五类这一历史概念的形成背景。This book explains the historical background behind the concept of the five black categories.