Unit 1 How can we become good learners?语法一.介词by的用法1.by意为“通过”，其后常接名词或动词-ing形式。用来表示“以、通过、用（某种方法或手段）”而达到某种预期的目的，常用来回答how引导的特殊疑问句。by doing sth意为“通过做某事”How does the boy improve his spoken English?By talking with a foreigner. (1)How do you learn English so well? chatting with my uncle in America online.A. By B. With C. In D.And(2)Jackson studied Chinese by _ tapes.A. listening B. to listen C. listening to D. to listening to 2.by+时间，意为“不迟于，在之前”I h
