Unit1 1
PartⅠ Text Exercises 1
PartⅡ Exercises for PRETCO 9
Unit2 17
PartⅠ Text Exercises 17
PartⅡ Exercises for PRETCO 24
Unit3 34
PartⅠ Text Exercises 34
PartⅡ Exercises for PRETCO 41
Unit4 49
PartⅠ Text Exercises 49
PartⅡ Exercises for PRETCO 56
Test yoursef(for Units 1-4) 64
Unit5 74
PartⅠ Text Exercises 74
PartⅡ Exercises for PRETCO 81
Unit6 90
PartⅠ Text Exercises 90
PartⅡ Exercises for PRETCO 97
Unit7 105
PartⅠ Text Exercises 105
PartⅡ Exercises for PRETCO 112
Unit8 122
PartⅠ Text Exercises 122
PartⅡ Exercises for PRETCO 130
Test yoursef(for Units 5-8) 140
Test yoursef(for PRETCO—Level B) 149