New words and expressions: break down 对......分类 sequence n. 一系列;一连串 vibrant a. 充满生气的;活跃的 core a. 核心的;最重要的 component n. 组成部分 browse v. 浏览 bubble v. 冒泡 cut it 达到要求;办成事 qualitative a. 质量的 Task 1: Listen to the audio clip “What Is a MOOC?" and fill in the blanks. What activities are usually involved for students to learn online? Watch short 1) ___________ and learn individual 2) ______________ ; Replay, pause or 3) _______ topics when necessary; Take short 4)_____________ or submit 5) ____________ ; Post, 6) _____________, and answer questions.