Unit 1 1
Unit 2 3
Unit 3 5
Unit 4 8
Unit 5 9
Unit 6 11
Review of units 1-6 13
Unit7 15
Unit8 17
Unit9 19
Unit 10 21
Unit 11 24
Unit 12 26
Review of units 7-12 28
Unit 13 29
Unit 14 31
Unit 15 34
Unit 16 36
Unit 17 38
Unit 18 40
Review of units 13-18 42
Unit 19 44
Unit 20 46
Unit 21 48
Unit 22 50
Unit 23 52
Unit 24 54
Review of units 19-24 56
参考答案 58
录音原文 67