存著再看年 10:34 Aliens, Time Travel, and Dresden – Slaughterhouse-Five Part 1: Crash Course Literature 212
存著再看年 12:20 Enols and Enolates – Reactivity, Halogenation, and Alkylation: Crash Course Organic Chemistry #43
存著再看年 09:42 The Reproductive Lives of Nonvascular Plants: Alternation of Generations – Crash Course Biology #36
