21世纪大学实用英语（第2版）综合练习 4PDF电子书下载

Unit 1 1

Part Ⅰ Text Exercises 1

Part Ⅱ Exercises for PRETCO 10

Unit 2 19

Part Ⅰ Text Exercises 19

Part Ⅱ Exercises for PRETCO 27

Unit 3 36

Part Ⅰ Text Exercises 36

Part Ⅱ Exercises for PRETCO 45

Unit 4 53

Part Ⅰ Text Exercises 53

Part Ⅱ Exercises for PRETCO 63

Test yourself（for Units 1-4） 72

Unit 5 80

Part Ⅰ Text Exercises 80

Part Ⅱ Exercises for PRETCO 90

Unit 6 98

Part Ⅰ Text Exercises 98

Part Ⅱ Exercises for PRETCO 106

Unit 7 115

Part Ⅰ Text Exercises 115

Part Ⅱ Exercises for PRETCO 124

Unit 8 132

Part Ⅰ Text Exercises 132

Part Ⅱ Exercises for PRETCO 140

Test yourself（for Units 5-8） 149

Test yourself（for PRETCO—Level A） 157