On 4th week of 6th unit from 9/20 to 9/26, Alvin organized meetings and taught lesson 16 on 9/25, meanwhile Nathan, Ethan and Emily joined as presenters. Lesson 13 had been taught by Nathan on 9/20, Lesson 14 had been taught by Ethan on 9/21, Lesson 15 had been taught by Emily on 9/23.
Reported by Alvin Zhou
