Unit 1 That must be a record！ 1
Unit 2 Crossing limits 15
Unit 3 The land down under 30
Unit 4 Green worlds 39
Unit 5 Getting the message 48
Unit 6 Going west 60
Unit 7 A Christmas Carol 69
Unit 8 Learning a foreign language 80
Unit 9 Health care 91
Unit 10 American literature 102
Unit 11 Key to success 111
Unit 12 Education 121
Unit 13 The mystery of the Moonstone 130
Unit 14 Zoology 139
Unit 15 Popular youth culture 149
Unit 16 Finding jobs 160
参考答案与提示 171