Contents 1
Lesson 1．Important Words 1
Lesson 2．Is Our World Getting Smaller? 5
Lesson 3．No Boots on 9
Lesson 4．The Law Is the Law but 12
Lesson 5．Lightning 16
Lesson 6．Do You Want a Good Memory? 20
Lesson 7．What Happens When You Sleep? 25
Lesson 8．The Golden Gate Bridge 29
Lesson 9．Underwater City 33
Lesson 10．The Search for New Evidence 37
Lesson 11．Master Craftman 42
Lesson 12．Ships—Important Means of Transport 47
Lesson 13．Living Together（1） 52
Lesson 14．Living Together（2） 58
Lesson 15．How Well Do You See?（1） 63
Lesson 16．How Well Do You See?（2） 69
Lesson 17．The Doctor s Story 74
Lesson 18．The Time to Learn（1） 80
Lesson 19．The Time to Learn（2） 87
Lesson 20．Age of New Materials 93
Lesson 21．Painting Aunt Polly s Fence 99
Lesson 22．The Marvels of Colour 106
Lesson 23．How Do Animals Know When an Earthquake IsComing? 111
Lesson 24．Rare Visitors 116
Lesson 25．Self-Protection 121
Lesson 26．Trial and Sentence 126
Lesson 27．Nature Note 132
Lesson 28．Once in a Lifetime 138
Lesson 29．One Man s Garden 143
Lesson 30．Heat Pollution and Noise Pollution 149
Appendix Ⅰ Phrases and Expressions 154
Appendix Ⅱ Proper Names 161
Appendix Ⅲ Vocabulary 166