Group 1 1
Group 2 11
Group 3 21
Group 4 30
Group 5 39
Group 6 48
Group 7 57
Group 8 66
Group 9 76
Group 10 86
Group 11 95
Group 12 104
Group 13 113
Group 14 123
Group 15 133
Group 16 141
Group 17 149
Group 18 158
Group 19 165
Group 20 172
Group 21 181
Group 22 190
Group 23 199
Group 24 208
附录1 单元练习答案与解析 217
附录2 词汇索引 281