Unit 15 Healthy eating 1
Unit 16 Fire！ 11
Unit 17 Nature 21
Unit 18 The necklace 32
Unit 19 Jobs 43
Unit 20 Mainly revision 52
Unit 21 Karl Marx 62
Unit 22 Britain and Ireland 71
Unit 23 Rescuing the temple 80
Unit 24 The science of farming 88
Unit 25 At the conference 98
Unit 26 Mainly revision 107
参考答案 116