Unit 13 The USA 1
Unit 14 Roots 24
Unit 15 Study Skills 50
Unit 16 Social and personal 78
Unit 17 My Teacher 102
Unit 18 Office equipment 131
Unit 19 New Zealand 155
Unit 20 Gandhi 182
Unit 21 A problem for the detective 209
Unit 22 Language of honey bees 238
Unit 23 The find of the century 266
Unit 24 Finding a Job 296
参考答案 328