Lesson 4 Cars and Trucks 第4课 小汽车和卡车 1. What is it? 1. 它是什么? car truck bus cab 小汽车 卡车 公共汽车 出租汽车 2. Let's sing a song. 2. 来唱一首歌。 The wheels on the bus go around and around, Around and arou...