Unit One 1
Lesson 1 Nature 1
Lesson 2 Life 5
Lesson 3 Animals 9
Lesson 4 Environment 13
Lesson 5 Review 1-4 18
Unit Two 25
Lesson 6 Invention 25
Lesson 7 Education 29
Lesson 8 Population 34
Lesson 9 Transportation 38
Lesson 10 Review 6-9 42
Unit Three 49
Lesson 11 Personality 49
Lesson 12 Friendship 54
Lesson 13 Travel 58
Lesson 14 Entertainment 62
Lesson 15 Review 11-14 66
Unit Four 73
Lesson 16 Geography 73
Lesson 17 History 78
Lesson 18 Languages 82
Lesson 19 Cultures 86
Lesson 20 Review 16-19 90
Unit Five 97
Lesson 21 Science and Technology 97
Lesson 22 Medicine and Health 101
Lesson 23 Customs and Habits 105
Lesson 24 Holidays and Festivals 109
Lesson 25 Review 21-24 113
Test Yourself 120
Key 133
参考书目 146