Home/chalkrailchalkrail/chawk-reyl/US // ˈtʃɔkˌreɪl //白垩纪,粉笔画,白垩纪的发展,白垩纪的发展历程Definitionsn.名词 noun1: a troughlike molding or strip holding chalk, erasers, etc., under a blackboard.Level 5Browse all words →