Unit 1 Past and present - 下载地址：8B Unit 1
Unit 2 Travelling - 下载地址：8B Unit 2
Unit 3 Online tours - 下载地址：8B Unit 3
Unit 4 A good read - 下载地址：8B Unit 4
Unit 5 Good manners - 下载地址：8B Unit 5
Unit 6 Sunshine for all - 下载地址：8B Unit 6
Unit 7 International charities - 下载地址：8B Unit 7
Unit 8 A green world - 下载地址：8B Unit 8