Unit 2 Language
一．重点单词短语
1代表 stand for 2 手势语 sign language
3 欣慰的微笑 a beaming smile 4 盘旋 fly in circles
5通知某人某事 inform sb.of/about sth 6在整个历史上 throughout history
7难以理解的规则 confusing rules 8 由…组成 consist of/be made up of
9由…发展起来的 develop from 10 官方语言 official language
