UNIT ONE 1
Text:Learning a Language 2
Exercises to the Text 5
Grammar Exercises 10
UNIT TWO 12
Text:The Story of Thanksgiving Day 15
Exercises to the Text 18
Grammar Exercises 23
UNIT THREE 25
Text:American Proverbs 27
Exercises to the Text 30
Grammar Exercises 34
UNIT FOUR 36
Text:A Case of Mistaken Identity 38
Exercises to the Text 40
Grammar Exercises 45
UNIT FIVE 48
Text:Quality Control 50
Exercises to the Text 53
Grammar Exercises 58
UNIT SIX 61
Text:Sharing Information 64
Exercises to the Text 67
Grammar Exercises 72
UNIT SEVEN 74
Text:Fast Food 78
Exercises to the Text 81
Grammar Exercises 86
UNIT EIGHT 89
Text:Smoking——Take It or Leave It 93
Exercises to the Text 97
Grammar Exercises 103
UNIT NINE 105
Text:Ecology——S.O.S 107
Exercises to the Text 109
Grammar Exercises 114
UNIT TEN 116
Text:Robots 119
Exercises to the Text 122
Grammar Exercises 127
UNIT ELEVEN 130
Text:Using Land Wisely（Ⅰ） 132
Exercises to the Text 135
Grammar Exercises 141
UNIT TWELVE 143
Text:Using Land Wisely（Ⅱ） 145
Exercises to the Text 148
Grammar Exercises 151
UNIT THIRTEEN 153
Text:Differences in Customs 156
Exercises to the Text 160
Grammar Exercises 166
UNIT FOURTEEN 168
Text:The Legacy 171
Exercises to the Text 174
Grammar Exercises 179
UNIT FIFTEEN 181
Text:Pollution——the Effects of Leads 184
Exercises to the Text 187
Grammar Exercises 191
Appendix 193